checkwhendone.comPut the habit on paper.
Print a tracker and hang it where you can't miss it. Check a box every time you follow through, and let the paper keep score.
Create your sheetFree · no account · prints on one A4 page
Schedule or simple
Pick your active weekdays and every box gets its real date, or keep it a plain numbered grid you fill at your own pace.
Always one page
A live A4 preview while you tweak. Whatever you set up is guaranteed to print on a single sheet.
Share as a link
The whole sheet lives in the URL. Send it to someone, or keep it to reprint the next batch with numbering continued.
Rules and QR codes
Add numbered daily rules below the boxes, and up to three QR-code links, like a demo video. Every sheet also prints a Print more code for quick reprints.
Why repetition?
How long does it take to form a habit?
There isn't a universal number.
In one real-world study, people repeated a new behavior daily in a consistent context. Among participants whose habit development could be modeled reliably, the median estimated time to reach 95% of maximum automaticity was 66 days. The middle half of estimates was roughly 39 to 102 days, and modeled estimates ranged from 18 to 254 days.
The takeaway isn't "66 days." Habit formation is gradual and highly individual. In the same study, missing one opportunity did not appear to materially disrupt the process.
CheckWhenDone does not promise that a habit will form after a certain number of checks. The checks help you repeat the behavior and make your progress visible.
Lally et al. (2010), How are habits formed: Modelling habit formation in the real world, European Journal of Social Psychology. DOI: 10.1002/ejsp.674