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The trend line, not today's number

Burn plots your raw weigh-ins and a seven day average on the same chart. The raw line jumps around. The average is the one that tells you which direction you are going.

Weight moves with fluid, food volume, salt and the time of day. Reading a single morning as progress is how people talk themselves out of a plan that is working.

7-day

Short-term direction

30-day

The one worth judging on

All-time

Since your first entry

Burn's Weight Trend chart showing a raw daily line and a smoother seven day average descending from 84 kg to 78 kg over three months

Burn's Weight Trend summary showing 78.1 kg current, a 7-day trend down 0.7 kg, a 30-day trend down 3.0 kg, an all-time change down 6.2 kg since 20 June 2026, and recent entries for 15 to 18 August

The summary

Three timeframes, so one bad morning cannot mislead you

Your current weight sits at the top, then the same movement measured over three windows. When the seven day figure disagrees with the thirty day figure, the thirty day one is the one to trust.

7-day trend

Noisy by nature. Useful for spotting a stall, not for judging a week.

0.7 kg

30-day trend

Long enough that fluid shifts average out. This is the number that answers whether the plan is working.

3.0 kg

All-time change

Dated from your first entry, so the figure means something specific rather than being a running total.

6.2 kg

The figures above are the ones shown in Burn's Weight Trend summary.

Why the average matters

Four consecutive mornings, from the screen above

Same time, four days in a row, and 0.9 kg down across them. Progress arrived unevenly: a drop, two identical mornings, then another drop.

15 AUG, 7:00

79.0 kg

16 AUG, 7:00

78.6 kg

17 AUG, 7:00

78.6 kg

18 AUG, 7:00

78.1 kg

A day with no movement is not a day with no progress. Glycogen is stored with water, and lower insulin during a fast means your kidneys release sodium and fluid, so the scale can hold still or rise while fat is coming off underneath.

Fasting for weight loss → Why fluid shifts →

Logging it

One entry a day is enough

Same time, same conditions, and the average does the rest.

WHEN

In the morning, before you eat

Every entry in the screen above is logged at 7:00. Keeping the time consistent removes one source of daily variation before it reaches the chart.

Your last weigh-ins, in a list

The most recent entries sit under the summary with their dates and times, and each one opens for a closer look.

ALONGSIDE THE FASTS

In the same Journal as everything else

Weight sits with your fasts, water, electrolytes and check-ins, so a month of consistency and a month of movement are visible on the same record.

The Journal → Best Weight Loss Week →

Weight is one measure among several

A scale cannot separate fat from fluid or muscle, and Burn does not claim to either. It records what you enter and shows you the direction over time. That the link between lower insulin, sodium excretion and fluid loss during fasting produces early scale movement is drawn from peer-reviewed research and traced in our evidence policy.

If tracking weight is not good for you

Daily weighing does not suit everyone. Burn works without a single weight entry. The weight-derived record simply stays unset, and the timer, stages and history are the same either way. Speak to a doctor before fasting if you have a history of eating disorders.

Watch the line, not the morning

Burn plots the raw entries and the seven day average together, with the movement measured over three timeframes.

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