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HumanizerBench

← July 2026 prompts

Business Email · GPT-5.5

Business Email · written by GPT-5.5 · 255 words · prompt business_email

0
passed at least 4 detectors
13
failed at least one detector
13
tools tested on this prompt
Winston AI
hardest detector, caught 13 of 13

Input passage

Generated by GPT-5.5; this exact text was pasted into every humanizer below.

Subject: Update: Annual Review Cycle Moving to April Hi team, I’m writing to let you know that we’ll be shifting our annual review cycle from December to April beginning this year. This change is intended to give everyone a more thoughtful and balanced review experience. December is often a busy period, with year-end deadlines, holiday schedules, planning activities, and personal commitments all competing for attention. Moving the review cycle to April will allow managers and team members to have more focused conversations, reflect on a fuller picture of performance, and better align goals with our business priorities for the year ahead. What this means in practice is that annual performance reviews, goal-setting discussions, and any related compensation or development conversations that would normally take place in December will now occur in April. We will share a detailed timeline, key dates, and guidance for preparing for the process well in advance. In the meantime, regular feedback and check-ins should continue as usual. Managers are encouraged to use upcoming one-on-ones to discuss progress, priorities, and development needs so there are no surprises when the formal review period arrives. Our goal is to keep performance conversations ongoing, transparent, and useful throughout the year—not limited to a single cycle. We understand this is a change, and we’ll work to make the transition as smooth as possible. If you have questions about how this impacts your goals, review timing, or planning, please reach out to your manager or HR. Thank you for your flexibility and continued commitment. Best, [Your Name]

How to read these scores

Each detector returns a human-likelihood on a common 0 to 1 scale, where 1 means it judged the text human-written and 0 means it flagged it as AI. On these pages a verdict counts as passed when that score is at least 0.50, the midpoint of the detector's own scale. That threshold exists only to draw the chips: the bypass rate on the leaderboard is the mean of each test's median score across the 5 detectors, a continuous number, so a tool's pass count and its bypass rate will not be the same figure.

Meaning is the input↔output embedding cosine and readability is a language-model writing-quality rating, both published per test in tests.json. Words is the output's length as a multiple of the input's; the scoring code penalizes ratios above 1.40 or below 0.60. Full definitions live in the methodology.

Humanized outputs

Ordered by how many detectors each rewrite passed; ties fall back to this cycle's rank. Each block shows what the tool returned and how the 5 detectors scored it.

Undetectable.ai

Rank #2 this cycle · run took 0:15

3/5 detectors passed
  • GPTZero1.00passed
  • Winston AI0.04caught
  • ZeroGPT1.00passed
  • Copyleaks0.00caught
  • Originality.ai1.00passed
Median
1.00
Meaning
94.7
Readability
45.0
Words
1.18× 255 → 302
Show output (302 words)

Subject: Update: Annual Review Cycle Moving to April Hi team, This year’s Annual Review cycle will occur in April rather than December. Annual performance reviews, setting of goals for the upcoming year and any corresponding salary increases or training will be more complete and beneficial if conducted in April instead of in December. The review cycle in April will enable us to more fully align the goals of our Team Members with the business objectives of the Company for the upcoming year. For those wondering what this change means for the Annual Performance Review (APR), all elements (annual performance review, goal setting, etc. related to compensation) will now occur in April instead of December. We will develop a great calendar of key dates with corresponding instructions to ensure everyone has sufficient time to prepare for their respective reviews. While the Annual Performance Reviews and Goal Setting discussions will now occur in April as part of the annual review cycle instead of December, Management intends for ongoing feedback and regular feedback to occur throughout the year. Thus, when scheduling one-on-one meetings with your team members, use those meetings to review progress, discuss priorities, and help to identify areas for development and that what you learn during the formal review process will not be a surprise. While changing the review cycle time is a big change we are committed to ensuring a smooth transition to the new annual review cycle time. If you have any questions regarding this change or would like to discuss the implications this will have on your current goals and those that you have for the upcoming review, as well as for how you can start to prepare for the review, please speak with your manager or HR representative. Thank you for your flexibility and continued commitment. Best, [Your Name]

Humanize AI Pro

Rank #3 this cycle · run took 0:10

3/5 detectors passed
  • GPTZero0.99passed
  • Winston AI0.00caught
  • ZeroGPT0.89passed
  • Copyleaks0.00caught
  • Originality.ai0.96passed
Median
0.89
Meaning
91.2
Readability
58.0
Words
0.86× 255 → 219
Show output (219 words)

Subject: Update: Annual Review Cycle to Be Moved to April Dear Team, I am writing to inform you that from this year onwards, we will be changing the annual review cycle to be conducted in April instead of December. The reason for making such a decision is that everyone deserves to get their review at a proper time in a more thoughtful way. December is always very hectic as it has year-end deadline pressure, holiday scheduling, planning activities, and many other things to do. Moving the annual review cycle to April will help everyone have proper conversations regarding performance and set up goals according to our business priorities for this year. This means that all annual performance reviews, goal setting discussions, and all other compensation and development discussion which used to happen in December will now happen in April. We will give you all information about the timeline and important dates to prepare yourselves for it. Until then, all of you should continue to give regular feedback and check-ins. Your managers will discuss all your priorities and development during one-on-one sessions. We hope that this change will not cause any difficulty to you and will make your conversation more effective. If you have any question regarding this matter, please feel free to contact your manager or HR. Thank You!

Stealth Writer

Rank #4 this cycle · run took 0:13

3/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.46caught
  • ZeroGPT1.00passed
  • Copyleaks1.00passed
  • Originality.ai1.00passed
Median
1.00
Meaning
95.8
Readability
62.0
Words
1.13× 255 → 287
Show output (287 words)

Description: The Annual Review Cycle is being moved to April.Subject: Update: April Annual Review Cycle! Hi team, As you may know, we are changing our annual review cycle from December to April, starting this year. This change is based to provide all with a more thoughtful and balanced review encounter. December can be a very busy time of the year with year-end deadlines, holidays, planning and other personal commitments vying for our priority. The change to April will provide managers and team members the opportunity to have more meaningful conversations, think through a more comprehensive view of performance and integrate goals with our business priorities for the upcoming year. In practical terms the implications are that Annual assessment, Goal setting discussions, and any other assessment or compensation related discussions that normally happen in December will now be in April. A detailed timeline, key dates and advice for preparing well for the process will be shared well before the process. Meanwhile, there should be no change to the frequency of feedback and check ins. In the run up to a formal review period, managers are encouraged to hold regular one-on-ones to check in on progress, priorities, and development needs; this way there are no surprises at formal review. We want to maintain an effective performance process that takes place throughout the year, rather than in one yearly cycle only and that remains transparent and effective for everyone. We know this is a change, and we will do our utmost to make it as easy on transition as possible. Any questions on the effect this has on goals, timing or planning should be directed towards your manager or HR. Thanks for your flexibility and continuous support. Best, [Your Name]

WriteHuman

Rank #1 this cycle · run took 0:14

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT1.00passed
  • Copyleaks0.00caught
  • Originality.ai0.99passed
Median
0.00
Meaning
92.6
Readability
52.0
Words
1.06× 255 → 270
Show output (270 words)

Subject: April Timing for Annual Reviews Dear all, As part of this year’s schedule, we would like to announce that the annual review cycle will now take place in April rather than continue in the previous cycle occurring in December. Considering feedback on the review experience, we felt that reviews conducted in December, a busy month, would be under a lot of pressure and could become more of a check the box exercise with all the competing priorities of year end, holiday plans, personal commitments, etc. Having the review in April allows for year-end reviews that are more meaningful, allow managers and employees to align a review of the goals and commitments for the year, consider the performance against review cycle priorities for the immediate year and allow for a focused and constructive analysis of the review. As previously noted, our annual reviews, discussions around review outcomes and related discussions on review outcomes and review related compensation in the review cycle will take place in April, and not December as was the practice before. We will provide a more detailed April 2024 review cycle plan with timing, key dates, and instructions for the review process well in advance. You can still have the ongoing performance feedback and the regular check-in reviews as part of this cycle. We are looking to make performance related feedback a more ongoing, open, and useful process. We appreciate your patience as we implement these review process changes. For more details on the review goals, timings, or plans, please connect with your people manager or HR. Thanks for your flexibility and your commitment. Best, [Your Name]

Humbot

Rank #5 this cycle · run took 1:08

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.08caught
  • ZeroGPT1.00passed
  • Copyleaks0.00caught
  • Originality.ai0.97passed
Median
0.08
Meaning
87.0
Readability
42.0
Words
1.19× 255 → 303
Show output (303 words)

You've been onboarded till October 2023 Hi team, The team will be moving out of the annual review cycle in December, and so I’m letting you know that we’ll be moving to April this year. This shift is meant to provide a more intentional and equally balanced experience for all involved in the review process. The busy month of December passes in which we should deal with year-end deadlines, holiday schedules and planning tasks as well as pulling time to spend with family. By moving the review cycle into April, it allows for more focused conversations between managers and their team members to reflect on a complete view of performance and align goals with our business priorities for the next 12 months. What this looks like in practice is that you will shift normal annual performance reviews, goal-setting conversations and any consequential compensation or development discussions typically held in December to April. If at the right time we will re-announced a detailed timeline and dates and how to prepare for process ahead of time. For now, business as usual; regular feedback and check-ins should go on. Managers can use these one-on-ones to review what their direct reports are working on, if they need support or guidance, and where their development needs lie so there is little chance of a surprise once it comes time for the formal review period. We wanted performance conversations to happen all year long, rather than in a compressed cycle. We appreciate this is step change, and we will do all that we can do to make the transition as smooth as possible. If you do have questions regarding how this will impact your goals, timing around reviews or planning to reach out to your manager or HR. Thank you for your flexibility and ongoing commitment. Best, [Your Name]

HIX Bypass

Rank #6 this cycle · run took 0:14

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.82passed
  • Copyleaks0.00caught
  • Originality.ai0.99passed
Median
0.00
Meaning
94.2
Readability
42.0
Words
1.09× 255 → 279
Show output (279 words)

Motion: Annual review cycle to April Hi team, Letting you know that, we will be moving our annual review cycle from December to April this year! This adjustment is meant to provide all with a more reflective and sensible review experience. With year-end deadlines looming, holiday schedules ramping up, planning activities galore and personal commitments to juggle, December can end up a sprint. Shifting the review cycle to April will give managers and team members space for productive conversation, context around preview performance on a more complete canvas, targeted alignment between goals and our work in support of our business priorities each year. Essentially this means that annual performance reviews, discussions about goals and any compensation or development related conversations would take place in December will now be held in April. Bid timetabling, important dates and general instructions to follow for preparing early will all be communicated well in advance. In the meantime, regular feedback and check-ins should carry on as normal. Manager tips: Use upcoming one-on-ones to check-in on how employees are tracking against their goals, where the focus is and what any development needs are in preparation for the formal review period ahead that includes related conversations so potential surprises later are avoided. We aim to make performance conversations perpetual, honest and helpful throughout the year rather than a annual cycle. We know this is a change, and we will do everything to make the minimal disruption be as smooth. If you have questions on how this affects your goals for the review period, timing or planning please reach out to your manager or HR. We appreciate your willingness to adapt and stay engaged. Best, [Your Name]

StealthGPT

Rank #8 this cycle · run took 0:23

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.87passed
  • Copyleaks0.00caught
  • Originality.ai1.00passed
Median
0.00
Meaning
94.0
Readability
68.0
Words
0.80× 255 → 204
Show output (204 words)

FYI: Annual Review Cycle moving to April. Team, Just to let you know, we will be transitioning our annual review cycle from December to April effective this year. This will ensure our performance process is more measured and well thought out. December is such a busy time for everyone: end of year deadline, holiday leave, planning, holidays and other obligations all make December not the best time to do annual reviews. Moving to April will give managers and employees more time to have thoughtful discussions about performance. This will affect annual performance reviews, goal-setting discussions and compensation discussions in our review. We will provide more details about dates and timelines when we’re ready. Regular reviews and conversations continue. Managers may use upcoming 1-1s to discuss performance, development and goals. We will continue to encourage ongoing performance conversations throughout the year to ensure that performance discussions are transparent, ongoing and beneficial to both the company and the employee. This is a change for us. We’ll do our best to make it work well for everyone. Please contact your manager or HR if you have questions about how this may impact your goal setting, reviews or plans. Thanks for your understanding and flexibility. Regards, [Your Name]

Super Humanizer

Rank #11 this cycle · run took 0:11

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.84passed
  • Copyleaks0.00caught
  • Originality.ai0.98passed
Median
0.00
Meaning
95.2
Readability
82.0
Words
1.02× 255 → 260
Show output (260 words)

FYI: Annual review cycle moving to April Hi team, I wanted to share that this year, we’ll be moving our annual review cycle from December to April. We hope this transition will offer a more balanced and intentional review experience for everyone. December is a packed month filled with year-end deadlines, holiday plans, company planning, and personal life, all of which compete for our attention. By moving our review process to April, we believe managers and their team members will be able to have more focused performance conversations, take a more holistic view of what was accomplished over the prior year, and more effectively align performance goals for the coming year. This means that annual performance reviews, annual goal setting, and any discussions around compensation or development that previously took place in December, will be rescheduled for April. You’ll be hearing much more from us soon, including details around a full timeline, key dates, and tips for preparing for this new process. In the interim, regular performance feedback and discussions continue! We encourage you to use your regular check-ins and one-on-one meetings with your manager to provide updates, discuss goals, and cover any development areas – so that there are no surprises in April. We aim for ongoing transparency in our performance discussions. We recognize this is a change and will support you through the transition. Please don’t hesitate to ask your manager or anyone on HR if you have questions on how this may affect your planning, goals, or review schedule. Thanks for your cooperation and dedication, [Your Name]

Walter Writes

Rank #7 this cycle · run took 0:21

1/5 detectors passed
  • GPTZero0.31caught
  • Winston AI0.00caught
  • ZeroGPT1.00passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
90.1
Readability
78.0
Words
1.09× 255 → 278
Show output (278 words)

Subject: Update – New Timeline for Annual Performance Reviews Hello Team, I wanted to inform you that we’re going to move our Annual Performance Review Cycle (APRC) from December to April. The APRC has historically occurred at the end of each year; however, with the numerous deadlines and commitments during December (e.g., holidays, deadlines, planning for the new year, etc.), it has become increasingly challenging for both managers and employees to provide meaningful evaluations and set realistic expectations for the next fiscal year. Therefore, by moving the APRC to April, we anticipate that managers will be able to engage in more thoughtful and meaningful conversations regarding employee performance and future goals/objectives aligned with the company’s strategic objectives. As such, the April cycle will include the annual performance evaluation, goal setting discussion(s), as well as any other developmental/compensation discussions that were previously scheduled for December. We will communicate a comprehensive timeline of key milestones/dates along with guidelines for preparing for the APRC prior to its commencement. Additionally, regular communication and feedback sessions will still be an integral part of our management culture. Managers are encouraged to utilize upcoming “one on ones” as opportunities to evaluate their direct reports’ progress, identify priorities and areas where additional development may be needed. This will enable us to maintain ongoing performance conversations which will be open, transparent and beneficial to both parties involved throughout the course of the year — rather than being confined to just one cycle per annum. Please do not hesitate to contact either your supervisor or Human Resources if you have any questions regarding the impact of these changes upon your performance goals, review cycle timelines or overall planning.

AI Humanize io

Rank #10 this cycle · run took 0:22

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.73passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
93.7
Readability
68.0
Words
0.87× 255 → 223
Show output (223 words)

Subject: Moving Our Annual Review Cycle to April Hey team, We want to let you know that we are moving our annual review cycle from December to April this year. We’ve found December to be a very hectic time of year, and it always feels jumbled by year-end deadlines, holiday schedules, planning activities, and personal commitments. Moving our review cycle to April will allow managers and team members to have more dedicated conversations, reflect on a fuller picture of performance, and better align goals for the new year with our upcoming priorities. This means that annual performance reviews, goal setting discussions, and related compensation or development discussions that would typically occur in December will now be happening in April. We will share an overview along with a timeline, key dates, and guidance for preparing for the process in advance of the process. In the meantime we want to emphasize regular feedback and check ins as usual; managers are encouraged to use upcoming one-on-ones to discuss progress, priorities, and development needs so that nothing comes as a surprise when the normal year-end review period comes. This is a change and we are committed to making it as smooth as possible. If you have immediate questions about how this affects goals and timing or planning for review, please reach out to your manager or HR.

NoteGPT

Rank #13 this cycle · run took 0:20

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.56passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
97.1
Readability
85.0
Words
0.87× 255 → 221
Show output (221 words)

Subject: Update: Annual Review Cycle Moving to April Hi team, Just a quick heads-up—we’re shifting our annual review cycle from December to April, starting this year. Why the change? December always feels packed, with year-end deadlines, holiday plans, and a whole list of things competing for your attention. By moving reviews to April, we’re hoping those conversations can be less rushed, more thoughtful, and actually useful for everyone. Managers and team members get more time to reflect, see the whole year’s performance, and set goals that match up better with where the business is going. So here’s what changes: all the usual stuff that happened in December—performance reviews, talking through goals, compensation, development plans—will now happen in April. We’ll send out a timeline and any prep materials well before things kick off. Until then, keep the regular feedback coming. Managers, use your one-on-ones to check in on progress and development, so there aren’t any surprises when review time rolls around. We want these conversations to stay open and helpful, not turn into a once-a-year formality. We get that change can bring questions, and we’ll help you adapt as smoothly as possible. If you’re wondering how this affects your plans or timing, don’t hesitate to ask your manager or HR. Thanks for rolling with us—and for everything you’re doing. Best, [Your Name]

Phrasly

Rank #9 this cycle · run took 0:17

0/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.39caught
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
95.1
Readability
82.0
Words
1.06× 255 → 270
Show output (270 words)

Annual Review Cycle Will Shift to April Hi team, We wanted to share that we will be moving our annual review cycle from December to April, effective this year. The purpose of this change is to allow more time for thoughtful and meaningful reviews. As you all know, December can be a hectic month with year-end deadlines, holiday schedules, planning projects and personal commitments. By moving this important discussion to April, we hope to allow managers and employees more time to thoughtfully discuss performance against goals for the year and align on business priorities for the upcoming year. In practice, this means that annual reviews, goal setting discussions, and any associated compensation or development discussions that currently occur in December will take place in April. A review schedule with key dates and outlines for preparing for the review process will be distributed well in advance. In the meantime, we expect that regular feedback and check-ins will continue throughout the year. We encourage managers to use upcoming one-on-ones to identify progress on current priorities and development plans so that there are no surprises when it comes time for the annual review discussions. Our aim is to ensure performance discussions are ongoing and meaningful all year long, not just during the annual review cycle. We recognize that this is a change from the norm and we will work to make this transition as seamless as possible. If you have specific questions related to how this impacts your current goals, timelines, and plans, please reach out to your manager and HR. Thank you for your flexibility and continued hard work. Best, [Your Name]

Grammarly

Rank #12 this cycle · run took 0:09

0/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.01caught
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
99.4
Readability
88.0
Words
1.00× 255 → 254
Show output (254 words)

Subject: Update: Annual Review Cycle Moving to April Hi team, I want to inform you that we will be moving our annual review cycle from December to April starting this year. This change aims to provide everyone with a more thoughtful and balanced review experience. December can be a hectic time, with year-end deadlines, holiday schedules, planning tasks, and personal commitments all demanding attention. Shifting the review cycle to April will help managers and team members have more focused conversations. It will also allow for better reflections on performance and clearer alignment of goals with our business priorities for the upcoming year. In practice, this means that annual performance reviews, goal-setting discussions, and any related conversations about compensation or development that usually happen in December will now take place in April. We will share a detailed timeline, key dates, and guidance for preparing for the process well ahead of time. In the meantime, regular feedback and check-ins should continue as usual. Managers should use upcoming one-on-ones to discuss progress, priorities, and development needs so there are no surprises when the formal review period comes. Our goal is to keep performance conversations ongoing, transparent, and helpful throughout the year—not just confined to a single cycle. We know this is a change, and we will do our best to make the transition smooth. If you have questions about how this affects your goals, review timing, or planning, please reach out to your manager or HR. Thank you for your flexibility and ongoing commitment. Best, [Your Name]

Session recording