Burn
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Burn
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Complete a fast every day for seven days. Accumulate 100 hours in a calendar month. Start within thirty minutes of the same time for fourteen days. You know exactly what you signed up for.
A challenge runs alongside your normal fasting. It does not change your schedule, it just counts something specific while you keep going.
The six
7
Complete a fast every day for 7 consecutive days. The simplest of the six, and the one completed in the screen below.
3
Complete 3 fasts of 20+ hours within a calendar month. Each one reaches two hours into Ketosis Entry.
14
Start your fast within 30 minutes of the same time for 14 days. About timing rather than length.
100
Accumulate 100 total hours of fasting within a calendar month. Seven 16:8 fasts across the month clears it.
100%
Complete every planned fast at 100% adherence for 7 consecutive days. Not one short fast in the run.
16:8
Seven days of 16 hour fasts. Seven days of 16 hour fasts, and the challenge running in the screen above.
When it goes wrong
The active card in the screen beside this reads 0 of 7, with the line: missed a 16h fast on day 1. Not a silent reset, and not a vague failure state. You know which day and which fast, so you know what to do differently.
A progress figure and a bar sit on the active card, so a challenge four days in looks different from one that has just started.
Available challenges each carry a Start control, so a challenge you did not finish is one you can pick up again from the same list.
A challenge is a layer on top of the record, not the record itself. Every fast you complete is stored at the length it reached whether the challenge survives or not.
CHALLENGES
A challenge asks for one measurable thing and leaves your schedule alone. You keep running whatever plan you were already on.
Pick one if you want a target that does not change your days.
PROGRAMS
A program sets what each day looks like across a fixed course or an ongoing pattern. Twenty-one of them, graded from Beginner to Experienced.
Pick one if you want the schedule decided for you.
Most of the six count days, timing or accumulated hours rather than how deep a single fast went, because which pattern a person can sustain matters more than which is theoretically optimal. That is drawn from peer-reviewed research and traced in our evidence policy.
Stop and eat if you feel unwell, whatever the challenge counter says. Burn maps elapsed time to named stages and does not measure ketosis, autophagy, or metabolic state.
Six challenges, each with its rule written on the card, and a completion date kept when you finish one.
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