WritingInstant, then a few seconds
Writing voice analyserWhat does your email writing say about you?
Paste two emails you have sent. Get your writing fingerprint, measured from the text rather than guessed, and one new email in your voice.
Spot the default
Two replies to the same email. Both were written by AI, including the one that reads like a person. One had a voice profile. One had nothing. You have twelve seconds.
- Free
- No account
- Twelve seconds a round
- Three lives
How it works
Three steps, no sign-up
Read the email
Each round opens on one situation a founder might face. Both replies answer it.
Pick the reply that had no profile
Both were written by AI. One was written against a description of how a specific person writes. The other was told nothing. You have twelve seconds to choose.
See why
The reveal names the tells in the default reply and the profile the other one followed. Right picks earn points and build a streak. A wrong pick or a timeout costs a life.
What you get
How the game scores
Everything here is fixed rules, nothing hidden. This is the whole scoring model.
| Part | Where it comes from | What it tells you |
|---|---|---|
| Points for a right pick | Fixed rules | (100 + 10 for every second left) × (1 + 0.25 for every pick in your streak), rounded. Deciding faster and keeping a streak both pay. |
| Lives | Fixed rules | Three. A wrong pick or running out of time costs one, and the run ends when they are gone. |
| Streak | Fixed rules | Resets to zero on a wrong pick or a timeout, and multiplies your next right one. |
| Best score | Fixed rules | Saved in this browser only. There is no leaderboard and nothing is sent anywhere. |
Background
Why it works this way
Why everyone's email started sounding the same
Two years ago your writing was yours. It had a rhythm, a set of words you overused, a way you opened when you were in a hurry. Now a large share of what arrives in any inbox has passed through a language model, and models have a house style.
That style is not bad writing. It is competent, grammatical, and characterless, because it is the average of everything ever written. It hedges, it balances, it says nothing in more words than nothing requires.
The result is that fluent, polished email has stopped being a signal of effort. If anything it can read as the opposite: the more perfectly balanced the paragraphs, the more likely nobody thought about you while writing them.
What the scarce thing is now
Writing that sounds like a specific person. Not better writing, not more correct writing. Recognisable writing.
That is the whole reason a voice profile exists. Ask a model to write an email and you get the average. Tell it that this person writes eleven-word sentences, never opens with a greeting, is blunt about money and never apologises for their prices, and you get something a reader will not flinch at.
The email you were not hunting in each round was written that way. The one you were hunting is what you get from every AI email tool that does not know who you are.
Limits
What it cannot tell you
Every tool here is a first pass with edges. These are this one's.
- It is not an AI detector. It tests one thing: whether you can tell a default-register reply from one written with a voice profile. Doing well here is not evidence you can spot AI text in general.
- Nothing here was written by a human. Every reply was generated. A version with one genuinely human option would be a better hook, but we could not build it honestly.
- Length is not a tell. The two replies in a round are matched on length before you see them, and a generated round is thrown away if it fails that check.
- A run can end early on material. If the supply of rounds runs out before your lives do, the run ends cleanly instead of repeating one.
Your data
What happens to what you give it
Read off the code that does it, not written from memory.
- In your browser
- The whole game. Your best score is saved in this browser and nowhere else.
- Sent to our server
- Only a request for a fresh round, carrying the topics of the last few rounds. Nothing about you.
- Sent on to a model
- Yes, to write new rounds while you play (Gemma through OpenRouter). You type nothing, so it sees nothing of yours.
- What we keep
- Nothing about you. A request counter tied to your IP address (30 rounds an hour) holds no content.
Questions
Questions people ask, answered plainly
10 answers, grouped. Each one is written against what the tool actually does.
Playing
How does scoring work?
A right pick scores (100 + 10 for every second left) times (1 + 0.25 for every pick already in your streak), rounded. So a fast, correct pick with a streak of three scores far more than a slow one at the start. A wrong pick or a timeout costs one of your three lives and resets the streak.
Is my score saved? Is there a leaderboard?
Your best score is saved in this browser only. There is no leaderboard and no account, so scores are not shared, compared or stored on our side.
Can I win by just picking the longer email?
You could at first, and people worked that out immediately, so the game was changed. The reply you are compared against is now chosen to be as close in length as the round allows (within about a fifth wherever it can be), and a generated round is thrown away if the two sides differ by more than a quarter, or if only the no-profile reply opens with a stock pleasantry. If you find another way to win without reading, that is a bug and we would like to hear about it.
About the emails
Were any of these written by a real person?
No, and that matters enough to say plainly. Every email in this game was generated. A version where one option is genuinely human would be a better hook, but we cannot build it honestly, and a site that claims a human wrote something a machine wrote has no business lecturing anyone about AI slop.
So what is the actual difference between the options?
Whether the model was given a voice profile. One of the two was written against a description of how one specific person writes: their sentence length, whether they greet by name, how blunt they are about money, what they never say. The other was written with no profile at all, in the register a model reaches for by default. Same brief, same model, one difference.
What are the tells?
Not the obvious ones. An email that opens by hoping this finds you well is easy, and a game built out of those would teach nothing. The replies here are the harder version: fluent, warm, plausibly human, and completely uncheckable. Nothing in the default one can be verified or argued with: no number, no date, no name, no version of events you could disagree with. If you finish reading and cannot repeat one fact back, that is the one.
Where do the rounds come from?
A set of stored rounds, plus new ones generated by a small AI model (Gemma, through OpenRouter) in the background while you play, so a run does not end early. A generated round that fails the fairness checks is discarded rather than shown.
Your data
Does the game send anything about me?
Only a request for a fresh round, which carries the topics of the last few rounds so you are not given repeats. You type nothing, so there is nothing of yours to send. We keep a request counter tied to your IP address, limited to 30 rounds an hour, which holds no content.
Why it matters
Why does this matter if the writing is technically fine?
Because people can feel it even when they cannot name it, and what they feel is that you did not write it. For a founder whose relationships are the business, an email that reads as generated says you did not think this was worth your attention. That is a worse outcome than replying slowly.
How do I stop sounding like the default one?
Write shorter, be specific, and cut every sentence that is managing how the message will feel rather than saying something. If you use an AI to draft, give it something real to work from: how you actually write, what you never say, who you are writing to. That is what a voice profile is, and it is the difference this game is testing.
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The other one is the point.
Mailient builds that voice profile from your own sent mail, then drafts every reply you owe on your real Gmail. The output is the kind you struggled to spot, because it is written as you rather than as nobody.