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Unbroken

Streak Calculator

Enter what you are counting and the day you started, and this gives you the day you are on — counted inclusively, so the start date is Day 1. It counts sessions as well as days, so a run held three times a week is not reported as a short one, and it names the next mark on the ladder: 7, 21, 30, 60, 90, 100, 180, 365.

Days banked 24 days 3 weeks and 3 days
Total Sessions 25 At the frequency below, from the start date.
Frequency Daily What one session is meant to be.
Started Aug 24, 2026 Day 1 of the run.
Weeks In 3 Whole weeks. The part week is in the line above.
Next milestone 30 days
21 30

6 days to go

Milestones

Every mark the counter knows, closed and open. Nothing here expires — a mark you reached stays reached.

The method

How the count is worked out

The whole page rests on one subtraction, and the subtraction is done in UTC on purpose. Both dates are reduced to a bare year, month and day, converted with Date.UTC, and the difference divided by 86,400,000. Doing it that way means a clock change cannot add or remove a day from your streak — the naive version of this sum loses a day every spring in half the world, and a tracker that quietly eats a day is worse than no tracker.

The count is inclusive: the start date is Day 1, so a run that began yesterday reads two days, not one. That is the off-by-one everybody argues about, and this page picks the reading a person uses out loud.

Sessions are counted separately from days, because a run held four days a week is not a shorter run. Daily is days + 1. Weekdays walks the range and counts Monday to Friday, so it is exact rather than an average. Three times a week, and any custom figure from one to seven, is whole weeks × sessions per week + whichever is smaller, the leftover days or the sessions per week — which is the honest floor, because a part week cannot be assumed to hold more sessions than it has days.

The equivalent-time line decomposes the total into 365-day years, 30-day months, 7-day weeks and the remainder. Those are reading units, not calendar units: 30-day months mean the phrasing stays stable rather than shifting because you started in February. The milestones are 7, 21, 30, 60, 90, 100, 180 and 365 days, and past a year the next mark is the next multiple of 365. That ladder is ours. Twenty-one days is on it because people look for it, not because habits are formed in it — that number traces back to a 1960 book about limb amputees adjusting to a missing arm, and it has never been a finding about anything else.

Unbroken counts days. It does not measure anything about your body, and nothing above is medical, nutritional or fitness advice. Where a number here is our own judgement rather than a published figure, the note says so and cites nothing. Method last checked 21 August 2026.

Why streaks matter

A streak is the simplest accountability tool that exists. Every day you show up, the number goes up. Every day you skip, it resets to zero. That's it.

Research shows that tracking streaks activates loss aversion — the psychological principle that losing progress feels worse than gaining it. This makes streaks one of the most powerful motivational tools available.

At 7 days, you've proven you can show up for a week. At 21 days, it starts to stick. At 66 days, research from University College London suggests it becomes automatic. And at 365 days, it's just who you are.

A fixed season does the same job from the other end. Instead of counting up from whichever day you happened to begin, everyone begins together and finishes together, so the number on the screen is the same number your friends are looking at. That is the whole design of the winter arc: when the winter arc starts has the dates and the 92-day count.

Count what you have banked here, then run the real thing in Unbroken — a 75-day pact your squad runs with you, where the ledger is automatic and yesterday cannot be edited.

The questions

Frequently asked questions

How does the streak calculator work?
Enter what you are counting, the day you started, and how often you do it. The calculator shows your current streak length, total sessions completed, and upcoming milestones.

Does it save my streak?
Yes, your streak data is saved in your browser's local storage. It persists between visits but is specific to this device and browser.

What milestones does it track?
The calculator highlights milestones at 7 days, 21 days, 30 days, 60 days, 90 days, 100 days, 180 days, and 365 days — the checkpoints where a run stops feeling temporary.

Can I count more than one thing?
This calculator counts one run at a time. To hold several daily tasks under one pact, with a ledger nobody can curate, use Unbroken.

What if I miss a day?
The calculator counts from your start date assuming no missed days. Unbroken handles misses honestly: the run restarts at Day 1, and it lands on your squad's board.
Next door

More tools

75 Hard Tracker

All six tasks, all 75 days, on one grid. Miss one and the grid starts again — that is the deal you are taking.

Lock-In Challenge Tracker

Set the rules, set the length, and stop deciding every morning. The calendar shows exactly how honest you have been.

30-Day Challenge Tracker

Thirty days is long enough to change something and short enough to finish. Pick the length, then hold it.

A streak you type in is a streak you can fake

Unbroken counts the days for you and puts them on a board your squad shares. No streak freezes, no repair purchases, no editing yesterday.

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