The five tests
A daily round is always Crossing, Stretch, Vanish, Between, then Aftertone. Each test scores 0–100. The day is the sum, out of 500, with a letter grade. Reveals stay on screen until you tap Next. A dragged or slid answer is never submitted just because you lifted your finger — only Confirm does that. Between is the exception: a single tap is the measurement itself. Between is fully playable with the sound off; its cue is a pair of visual flashes.
Scoring curves Initial value
Every constant on this page is an initial design value. A game day’s scoring is fixed on the morning that day opens in the eastern United States; later retunes apply only to future days and never change a day that has already been published. The curves are written so a mid-size miss still leaves a readable score: they are not the kind of rule where a 9% error collapses to two or three points, and they are not a cliff that drops a fair miss straight to zero. A truly large miss can still round to 0, and that is intentional.
Crossing
The error is the distance from your mark to the true intersection, divided by the short side of the canvas. A miss inside 2% of that short side scores 100. The Gaussian width σ is 8% of the short side. Initial value
score = round(100 × exp(−0.5 × (max(0, error − 0.02) ÷ 0.08)²))| Error, as a fraction of the short side | Score |
|---|---|
| 0% | 100 |
| 2% | 100 |
| 4% | 97 |
| 6% | 88 |
| 10% | 61 |
| 14% | 32 |
| 18% | 14 |
| 26% | 1 |
Stretch
Stretch uses a log-ratio, so making the bar twice as long and making it half as long are the same mistake. A guess within 6% of the true path length scores 100. The decay coefficient is 1.6. A double (or a half) scores 36. This is the same philosophy Howbigle uses for real-world sizes; here it applies only to a path on the canvas. Initial value
score = round(100 × exp(−1.6 × max(0, |ln(guess ÷ true)| − ln(1.06))))| Your bar as a factor of the true path | Score |
|---|---|
| Exact | 100 |
| 1.06× or about 0.94× (6%) | 100 |
| 1.1× or 0.91× | 94 |
| 1.25× or 0.80× | 77 |
| 1.5× or 0.67× | 57 |
| 2× or 0.50× | 36 |
| 3× or 0.33× | 19 |
| 5× or 0.20× | 8 |
| 10× or 0.10× | 3 |
Vanish
Same shape as Crossing: the error is the distance to the true vanishing point, divided by the short side of the canvas. The perfect window is a little wider (3%) and σ is 10%, because a perspective target is softer than a geometric intersection. Initial value
score = round(100 × exp(−0.5 × (max(0, error − 0.03) ÷ 0.1)²))| Error, as a fraction of the short side | Score |
|---|---|
| 0% | 100 |
| 3% | 100 |
| 6% | 96 |
| 10% | 78 |
| 13% | 61 |
| 18% | 32 |
| 23% | 14 |
| 33% | 1 |
Between
The error is the absolute time, in milliseconds, between your tap and the midpoint of the two flashes. A tap inside 30 ms scores 100. The Gaussian width σ is 120 ms. Being a few dozen milliseconds late does not drop you to zero. Initial value
score = round(100 × exp(−0.5 × (max(0, |tap − midpoint| − 30) ÷ 120)²))| Timing error | Score |
|---|---|
| 0 ms | 100 |
| 30 ms | 100 |
| 60 ms | 97 |
| 90 ms | 88 |
| 150 ms | 61 |
| 210 ms | 32 |
| 270 ms | 14 |
| 390 ms | 1 |
Aftertone
The error is the absolute difference in linear lightness, on a 0–100 scale, between your match and the true gray. A miss inside 3 points scores 100. σ is 12. The reveal is about the illusion, not a humiliating score: a moderate lightness miss still leaves a readable number. You may view the sample a second time; that extra look does not cap your score. Initial value
score = round(100 × exp(−0.5 × (max(0, |Lguess − Ltrue| − 3) ÷ 12)²))| Lightness error, 0–100 | Score |
|---|---|
| 0 | 100 |
| 3 | 100 |
| 6 | 97 |
| 9 | 88 |
| 15 | 61 |
| 21 | 32 |
| 27 | 14 |
| 39 | 1 |
Letter grades
Grades are applied to each test’s 0–100 score, and to the daily total as a percentage of 500 (so 450 is an S, the same as a 90 average).
| Grade | Score (out of 100, or % of 500) |
|---|---|
| S | 90–100 |
| A | 80–89 |
| B | 65–79 |
| C | 50–64 |
| D | 30–49 |
| F | 0–29 |
Share cards, streaks, and the archive
A share is the puzzle number, your total out of 500, five color squares (96+ green, 80+ yellow, 60+ orange, 30+ red, otherwise black), a streak line when the streak is at least two days, and instinctle.com. It never includes a coordinate, a length, a time, or a lightness.
A new set arrives at midnight in the eastern United States (America/New_York), including daylight-saving changes. Unlimited practice and the archive do not change that day’s official score or your streak.
Your streak and best score
Instinctle does not ask you to log in. Your daily result, your streak, and your best total live in this browser’s local storage. Clearing the site’s data, or switching devices, will erase them. Unlimited practice and archive replays do not change your daily score or streak.
Play today’s five ↗A few things you might wonder
Is Instinctle the same as Perceptle or Freehand?
No. Instinctle is an independent daily perception game with five original tests, its own scoring, and its own visual style. It is not affiliated with, endorsed by, or a copy of Perceptle or Freehand.
How is my score calculated?
Each test scores 0–100 on a published curve with a small perfect-score window, then a smooth falloff. Pointing tests use a Gaussian on the distance to the true point. Stretch uses a log-ratio, so twice as long and half as long score the same (36). Between uses milliseconds, Aftertone uses lightness points. The constants are initial design values, labelled as such on the How to play page, and will be frozen after an internal playtest. Five tests make a total out of 500.
When does the daily puzzle change?
At midnight in the eastern United States (America/New_York), including daylight-saving changes. Unlimited practice is available at any time and does not change your daily score or streak. Replaying a past day from the archive also leaves today’s official score alone.
Do I need an account? Where is my streak kept?
No account is required. Your daily scores, streak, and best total are saved in this browser on this device. Clearing the site’s data will reset them. Switching devices will not carry them over.
Can I play Between with the sound off?
Yes. Between’s main cue is a pair of visual flashes. A short optional beep can sit on top, but the flashes, the interval, and the scoring are unchanged when the site is muted or the device is silent.
Is this a medical vision or hearing test?
No. Instinctle is a casual daily game about perceptual instinct. It is not a clinical test, a diagnosis, or a substitute for professional care.