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HumanizerBench

← August 2026 prompts

Business Email · Claude Sonnet 5

Business Email · written by Claude Sonnet 5 · 273 words · prompt business_email

0
passed at least 4 detectors
12
failed at least one detector
12
tools tested on this prompt
Winston AI
hardest detector, caught 12 of 12

Input passage

Generated by Claude Sonnet 5; this exact text was pasted into every humanizer below.

Subject: Exciting News: We're Moving to a Four-Day Work Week! Hi Team, I'm thrilled to share some big news: starting next quarter, we're officially transitioning to a four-day work week! This decision comes after careful consideration and reflects our commitment to your wellbeing and work-life balance. We believe that a shorter work week will not only improve quality of life but also boost creativity, productivity, and job satisfaction across the board. **Here's what you need to know:** Starting [specific date], our standard work week will run Monday through Thursday, with Fridays off. Full-time employees will maintain their current salary and benefits—this is not a reduction in compensation, just a reduction in scheduled work days. **What this means for you:** - Standard work hours will be [insert details, e.g., "adjusted to 9 AM–6 PM to maintain full weekly hours" or "remain the same, condensed into four days"] - All existing PTO, holidays, and benefits remain unchanged - Client-facing teams should coordinate coverage to ensure we maintain service standards - Team meetings and key collaboration times will be scheduled within our new four-day window **Next steps:** Over the coming weeks, department leads will work with you to ensure a smooth transition. We'll also be gathering feedback throughout the first quarter to make adjustments as needed. Please don't hesitate to bring questions or concerns to your manager or to me directly. This is a big change, and we want to get it right together. I'm confident this shift will benefit both our team and the business as a whole. Thank you for your continued hard work and flexibility. I'm excited for what's ahead! 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.

Phrasly

Rank #7 this cycle · run took 0:19

3/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.01caught
  • ZeroGPT0.83passed
  • Copyleaks1.00passed
  • Originality.ai1.00passed
Median
0.83
Meaning
94.4
Readability
58.0
Words
1.03× 273 → 282
Show output (282 words)

Subject: Four-Day Work Week Starting Next Quarter! Hi Team, Today I am thrilled to announce that we have decided to make the switch to a four-day work week, effective next quarter! We know many of you have been asking for this and we have finally decided that it’s the right time to do it. We hope that this new schedule will give everyone a better quality of life and allow you to be more creative, productive and happy. Here are some details: Beginning on [insert date], our work week will be Monday thru Thursday with Friday as a regular day off. This is FULL TIME. Salaries and benefits will not change --only the number of days that you are scheduled to work. Your Work Day: *Hours may be from [insert here. Eg. adjusted to 9 AM-6 PM with lunch to equal full week hours]" or "will remain the same, you will just work four days instead of five." *PTO, holidays, etc. will not change *If you are client facing, you will need to work with your team to ensure there is coverage for clients *All team meetings will be held during the four day work week. Over the next several weeks, we will work with each team to finalize the logistics. We will also solicit feedback from you all during the first quarter to see how this is working. As always, if you have any questions or concerns, please do not hesitate to speak with me or your manager. I know this is a big change, but we are confident that it will benefit not only our employees, but our business overall. Thank you for all that you do! Best, [Your Name]

Walter Writes

Rank #9 this cycle · run took 0:21

3/5 detectors passed
  • GPTZero1.00passed
  • Winston AI0.06caught
  • ZeroGPT0.82passed
  • Copyleaks0.00caught
  • Originality.ai1.00passed
Median
0.82
Meaning
90.0
Readability
65.0
Words
1.08× 273 → 294
Show output (294 words)

Subject: Update: New Four-Day Workweek Starting Next Quarter Dear Team, We have an exciting announcement: starting next quarter, we are going to implement a four day workweek (Monday thru Thursday). After researching and discussing how much time people spend at work and the effects on their well-being, family, and health, we decided to try something new. We think that reducing the number of days worked will give us all more free time, help create more creative ideas, increase productivity, and overall make everyone happier working here. Below is a list of things you need to know: * The last day of a five day workweek will be [date]. * The new work schedule will start on the following Monday. * Our office will be closed every Friday. * We are not cutting anyone’s pay or benefits – simply the amount of time they work per week. Here are some additional points regarding the changes: * Your regular working hours may vary depending on the nature of your position. Some positions may require you to continue to work a set number of hours each week. For example, if someone works from 8 am to 5 pm Mon – Thurs, they would still be working the same number of hours. However, since there are less hours being worked over a longer period of time, that person could possibly leave earlier than usual on those days. * Your PTO/Holiday/Sick Leave/Benefits will NOT be affected in any way by this change. * As client facing departments, you will need to plan so that your services do not suffer when you are gone. Departments can determine who needs to cover responsibilities while others are off. * Departmental meetings/and other collaborative events will occur during the four days of operation.

WriteHuman

Rank #1 this cycle · run took 0:19

2/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.89passed
  • Copyleaks0.00caught
  • Originality.ai1.00passed
Median
0.00
Meaning
93.7
Readability
57.0
Words
1.19× 273 → 324
Show output (324 words)

Subject: Four-Day Work Week! Hi Everyone, This is HUGE NEWS! As of next quarter, we will be switching to a four-day work week. We understand that the work-life balance has been on your mind. It has been on ours too. This change is something we have been thinking about and something we feel will improve work-life balance, while also improving mental health and productivity at work. Here are some important details: Make sure you mark your calendars for [specific date]. This will start the changeover for the four-day work week where we will be working Monday through Thursday and have Fridays off. Our full-time employees will keep their usual salary and benefits and this will not be a decrease in pay. Here are some changes to think about: - Your daily hours may change to... [what the new hours will be... e.g. a shift in start and end time for the day, or leaving and starting work at the same time for all the new, shorter, work days]. - PTO won't be changed and you aren't losing any holidays. - If you work with the public and do client meetings, you will need to plan ahead so we still offer services that are helpful to everyone. - Even though we only work four days, we will still plan team meetings and collaboration days that will help us work better and improve productivity. There are some things your managers can help you with during this transition and we will reach out to collect feedback and see if we can make any changes. Please bring any concerns or questions you have to your Manager or to me directly. We appreciate your assistance with this large undertaking. I am wanting to push this particular change through for both the team and the business's greater good. We continue to appreciate your hard work and flexibility. There are exciting times ahead and we are all enthusiastic! Best, [Your Name]

Humanize AI Pro

Rank #2 this cycle · run took 0:17

2/5 detectors passed
  • GPTZero1.00passed
  • Winston AI0.01caught
  • ZeroGPT1.00passed
  • Copyleaks0.00caught
  • Originality.ai0.02caught
Median
0.02
Meaning
89.1
Readability
45.0
Words
1.03× 273 → 282
Show output (282 words)

Subject: Great news! We'll be working on the four-day-week schedule! Hi all! It is time to tell you that starting from the next quarter we are going to move to a four-day-week schedule! It took us some time and thorough discussion before we decided to go in this direction. But now we believe that it is the right move that will improve your quality of life as well as will give additional push for productivity and creativity! **The main details to be noted:** As of [the exact date], our work schedule will look like that: Monday, Tuesday, Wednesday, and Thursday, Friday being day off for the full-timers. The salary and other benefits will not be reduced in any case. It is just the number of the workday we reduce. **What you may expect to change:** - The work hours will be set to [put here the new work hours] - The number of the PTO days and holidays will remain unchanged - It is necessary to arrange client-service staff properly in order to provide the service standards - The team meetings and important collaborations have to take place in this work schedule too **Next steps:** Over the following weeks we, together with the heads of the departments, will discuss everything and will make it clear how this process will go on. During the first quarter, we are going to collect and analyze your opinion on it. Please do not hesitate to contact your manager or me about any concerns you may have. This change is great opportunity for us all and I am sure that it will help our business too! Thank you for all efforts you take and for being flexible!

AI Humanize io

Rank #6 this cycle · run took 0:21

2/5 detectors passed
  • GPTZero1.00passed
  • Winston AI0.01caught
  • ZeroGPT0.81passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.01
Meaning
87.9
Readability
62.0
Words
0.71× 273 → 194
Show output (194 words)

Subject: Announcing the Transition to a Four-day Work Week. Hello Team, I'm excited to let you know that we are going to implement a remarkable change this year – the introduction of a four-day work week. We came to such a decision after weighing all the pros and cons. The shortened work week will allow our employees to enhance their lives and professions. Here's what you need to know: Starting from [insert date], Fridays will not be your working day. Your salary remains unchanged. Thus, the reduction of work hours does not imply any deduction from your salary. In other words: - You will keep your usual working hours. - Your holiday pay will remain unchanged. - Those employees whose work involves direct contact with customers will have to organize their schedule accordingly. - Other meetings will take place during the regular working days. Next steps: In a few weeks, you will be provided by your team leaders with all necessary information. We will use a feedback mechanism during the implementation of the new policy. Please, ask your manager or me for help in case of any problem. We hope everything will go smoothly!

Undetectable.ai

Rank #8 this cycle · run took 0:19

2/5 detectors passed
  • GPTZero0.99passed
  • Winston AI0.05caught
  • ZeroGPT0.94passed
  • Copyleaks0.00caught
  • Originality.ai0.02caught
Median
0.05
Meaning
91.6
Readability
38.0
Words
1.56× 273 → 426

Output is more than 1.4× the input length, penalized as length inflation.

Show output (426 words)

Subject: New Four Day Work Week - Starting Next Quarter Hi Team, BIG NEWS HERE AT F45 HQ. As we head into the new quarter we will be transitioning to a FOUR DAY WORK WEEK for all employees. The four day workdays will allow us to improve the Work at Work initiative’s goal of ensuring that WorkNet team members’ overall quality of life is going up while their creativity, productivity and job satisfaction are going up too. **Here's what you need to know:** The four day one of the four-day work week will begin on the first of the next quarter. We will work four days a week, Monday through Thursday, and we will be off on Fridays. We will still be considered full-time employees and we will maintain the same salary and benefits that we have now. **What this means for you:** - Hours: The hours that we work will be adjusted to 9 AM–6 PM in order to ensure that we still work the same number of hours over the four days of the week. - All PTO, Holidays and Benefits will remain the same. - Client-facing teams will need to work out how best to cover for all days of the week in order to maintain their service standards. —as currently. — Team meetings & major collaboration will be scheduled within the four days of the week. - All Team meetings and key collaborations will be set within the four days of work. — Full-time employees will continue to receive the same salary and same benefits and this is NOT be a reduction in pay and benefits. **Next steps:** Department Leads will work with each department individually to create a plan for transitioning their teams to the 4 day work week model. Throughout the first quarter we will be soliciting feedback from all employees in order to make any necessary changes to ensure the goals of the 4 day work week model are being met. Any questions or concerns should be sent to your manager or to me directly. This is not a cut in salary or benefits – it’s a change in schedule. We hope that the management team are as confident that this change will be good for the business as we are that it will be good for all employees of the business. Your hard work and flexibility in trying to make this all work is not going to go unnoticed and I am super excited to be moving in this new direction of our company’s growth. Best, [Your Name]

Stealth Writer

Rank #3 this cycle · run took 0:15

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.28caught
  • ZeroGPT0.96passed
  • Copyleaks0.00caught
  • Originality.ai0.02caught
Median
0.02
Meaning
94.3
Readability
38.0
Words
1.24× 273 → 338
Show output (338 words)

Meet the need for a creative and exciting subject for both staff and students by taking them on a journey to a better tomorrow with a Four-Day Work Week! Hi Team, I want to let you know about some exciting news: Beginning next quarter, we are switching over to a four day work week! This is a well thought out decision and is in the interest of your wellbeing and work-life balance. We are convinced that the reduction of the working week will not only have an effect on the quality of life but also on the creativity and productivity of everyone, as well as on job satisfaction generally. Here's some information you should know: Our work week will begin as Monday - Thursday with Fridays being a day off beginning [specific date]. This will NOT be a decrease in compensation--full-time staff will continue to work their current salaries and benefits just with a reduced number of days scheduled to work. It will impact you in the following way: When the standard hours are going to change, they will be [insert details, e.g., "adjusted to 9 AM-6 PM for full hours throughout the week" or "will remain the same, however, put into a 10/4 schedule"] Existing PTO, holidays and benefits stay the same. - Client facing teams to coordinate cover to make sure we meet our service standards Team meetings and important team collaboration periods will be held in our new 4-day window **Next steps:** The Department leads will be touched on by you and make it smooth for the upcoming weeks. We'll also be gathering feedback throughout the first quarter to make adjustments as needed. Feel free to come with questions or concerns to your Manager or straight to me. It's a great shift, and we want to get it right together. I'm sure this transition will work to our team's advantage and the company's advantage. Thanks for all your hard work and flexibility. I look forward to the new things that are coming! Best, [Your Name]

HIX Bypass

Rank #4 this cycle · run took 0:15

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.20caught
  • ZeroGPT0.97passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
91.0
Readability
28.0
Words
1.10× 273 → 300
Show output (300 words)

You get to have this sentence or you will be paid: ✏️ Subject: This is Brilliant! We are going for Four Day Work Week. Hi Team, I am excited to announce that starting next quarter, we are moving into a four-day work week! It has been made following extensive deliberations on the wellbeing of our teammates given their partnerships, families and contests for work-life balance. We think short work week is not just about quality of life, but it will also spur creativity and productivity — and job satisfaction across the board. Here's what you need to know: Effective [date] our normal work week will consist of Monday to Thursday, with Fridays off. Full-time employees will keep their salary and benefits as is — this isn't a pay cut, just a work week reduction. What this means for you: Your standard work day will be [insert clause, e.g. "modified to 9 AM–6 PM to give you a full week of hours," or — in the event that you're packing it all into four days] Your existing PTO, holidays and benefits remain the same Coverage across client-facing teams to ensure that we get coverage around service levels. Team meetings and important overlap will be scheduled inside of our new four day window Next steps: In the coming weeks, department leads will be collaborating with you to make your process transition seamless. During the first quarter of 2023 we will also be collecting feedback to adjust accordingly. Do not take any question or concern to your manager. That is a major shift, and we want to do it together right. I'm positive this change will be good for our crew and the company at large. Thank you for your consistency and flexibility in work. I'm excited for what's ahead! Best, [Your Name]

Humbot

Rank #5 this cycle · run took 0:32

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.03caught
  • ZeroGPT0.85passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
92.4
Readability
42.0
Words
1.15× 273 → 314
Show output (314 words)

TEACHER MANAGERSSubject: We Have Some Exciting News — We're Going to a 4-Day Work Week! Hi Team, I have some exciting news to share, we cautiously starting next quarter will be a 4-day work week company! This decision does not come lightly and it is made in the best interest of you as well as your mental health. The shorter the work week, the better life will be — and we believe that with our whole hearts. It will also increase creativity, productivity and job satisfaction for all of them. Here's what you need to know: As of [insert date], we will have a normal working week from Monday to Thursday (Friday off). Full-time workers will keep their same salary and benefits—this is not a cut in pay, simply cut hours worked per week. What this means for you: Normal working hours (i.e. the hours for [insert details; e.g. "will be adjusted to 9 AM–6 PM to ensure all the weekly hours are maintained," or "remain unchanged, condensed into four days"]) You will continue to have all PTO, holidays and benefits as before Client facing teams should coordinate coverage to ensure we maintain service levels The four-day window will schedule for team meetings and important collaboration times Next steps: As department leads will work with you over the next weeks to make a smooth transition. The first launch will allow for some early feedback over Q1 to refine as necessary. As always, if you have any questions or concerns, please feel free to raise them with your manager or me directly. That's a significant shift and we want to get it right together. If anything, I know that this adjustment is going to be great for our team and company as a whole. And thank you for continuing to work hard and quickly pivoting around everything! I'm excited for what's ahead! Best, [Your Name]

Super Humanizer

Rank #10 this cycle · run took 0:20

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.58passed
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
97.1
Readability
80.0
Words
1.04× 273 → 284
Show output (284 words)

Subject: Big News – We’re Moving to a Four-Day Work Week! Hey Team, I’m incredibly excited to announce a significant update: starting next quarter, we’re officially implementing a four-day work week! This decision was the result of much deliberation, and it demonstrates our ongoing commitment to your well-being and a healthy work-life balance. We truly believe a compressed work schedule will not only enhance personal quality of life but also inspire greater creativity, productivity and overall job satisfaction for everyone. Here's the rundown: Effective [Date], our new standard work week will be Monday through Thursday, with Fridays fully off. All full-time employees will receive the same compensation and benefits, reflecting this change as an optimization of our time, not a reduction. What This Means For You: Standard operating hours will be adjusted (insert specific, e.g., “to 9AM-6PM to accommodate standard hours” or “to remain 9AM-5PM”) All currently available PTO, holidays, and benefit programs remain unaffected Customer-facing teams will coordinate to ensure a seamless customer experience on all days Essential collaborative meetings and client engagements will be scheduled strategically within our new four-day framework What Happens Next? Your department leads will guide you through this transition over the next few weeks. We will actively solicit your feedback throughout the first quarter as we implement the new structure, making any necessary adjustments to optimize the program. Please feel comfortable reaching out to your manager or me directly with any questions or concerns. This is a bold and exciting move, and we know its success depends on us working together. I’m enthusiastic about the positive impact this change will have on our team and the business. Thank you for your continued dedication and agility! Best, [Your Name]

StealthGPT

Rank #12 this cycle · run took 0:30

1/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.53passed
  • Copyleaks0.00caught
  • Originality.ai0.22caught
Median
0.00
Meaning
94.2
Readability
55.0
Words
0.89× 273 → 242
Show output (242 words)

Subject: Good News – We're Switching to a Four-Day Work Week! Hey everyone, Big news: next quarter we're switching to a four-day work week! We've been thinking about this for a while and have decided to take the leap. A four-day work week can increase employee productivity, quality of life, and job satisfaction while reducing burnout and improving focus and creativity. The details From [date], the work week will be from Monday to Thursday. Salaries and benefits will not be reduced. This is simply a four-day schedule with no change to pay. How does this affect you? Working hours will be [insert details, e.g. "reduced to 9am - 6pm", or "unchanged"] Holidays and time off remains the same We expect client services teams to coordinate coverage to ensure continuity of service We will continue to hold our regular meetings and focus on core activities during the four day week What happens next? Department heads will reach out to you in the coming weeks to help make sure the transition runs smoothly. We will also be collecting feedback over the next quarter to ensure we make any necessary changes along the way. Feel free to discuss anything you'd like with your manager or myself. It's a big change and we want to get it right together. I have no doubt that it will be a positive step for both our people and our business. Thanks for your dedication and your support! Cheers, [Name]

Grammarly

Rank #11 this cycle · run took 0:13

0/5 detectors passed
  • GPTZero0.00caught
  • Winston AI0.00caught
  • ZeroGPT0.02caught
  • Copyleaks0.00caught
  • Originality.ai0.00caught
Median
0.00
Meaning
99.3
Readability
80.0
Words
1.00× 273 → 273
Show output (273 words)

Subject: Exciting News: We're Moving to a Four-Day Work Week! Hi Team, I'm excited to share some big news. Starting next quarter, we will officially switch to a four-day work week. We made this decision after careful thought. It shows our commitment to your well-being and work-life balance. We believe that a shorter work week will improve quality of life and also boost creativity, productivity, and job satisfaction. **Here's what you need to know:** Starting [specific date], our standard work week will run from Monday to Thursday, with Fridays off. Full-time employees will keep their current salary and benefits. This is not a pay cut, just fewer scheduled work days. **What this means for you:** - Standard work hours will be [insert details, e.g., "adjusted to 9 AM to 6 PM to maintain full weekly hours" or "remain the same, condensed into four days"]. - All existing PTO, holidays, and benefits will stay the same. - Client-facing teams should coordinate coverage to maintain service standards. - Team meetings and key collaboration times will be scheduled within our new four-day week. **Next steps:** In the coming weeks, department leads will work with you to ensure a smooth transition. We will also gather feedback during the first quarter to make changes if necessary. Please feel free to share any questions or concerns with your manager or directly with me. This is a big change, and we want to make it work well for everyone. I am confident this shift will benefit both our team and the business. Thank you for your hard work and flexibility. I am looking forward to what’s ahead! Best, [Your Name]

Session recording