Is the target date exact?

It's an estimate. Plan 10–20 % buffer and accept that your body has phases.

What pace is healthy?

0.5–1.0 % of body weight per week. For most people, 0.5 kg/week is the ideal anchor.

Should I plan diet breaks?

Yes for phases longer than 8 weeks — 1–2 weeks at maintenance help mentally and hormonally.

Wait 2 weeks. Then either add steps or drop calories by 100 — not both at once.

Calculator · Performance Lab

Diet Duration Calculator

How long your diet takes at your chosen pace — estimated realistically.

Ergebnis

Duration: 14.0weeks
Estimated target date: October 12, 2026
Change: 7.0kg
Equivalent daily deficit: 550kcal/day

Important: the estimate is linear, your body isn't. Metabolic adaptation, plateaus and diet breaks extend the real duration.

Explained

What this calculator does for you

Diets rarely fail because of math — they fail on unrealistic timelines. Plan a diet as 'a few weeks' and you'll be disappointed. Plan it as 3–4 months and you'll make it.

The calculator turns your chosen weekly rate into a duration in weeks and months plus a rough target date. It also shows the daily deficit that rate implies.

Important: it's linear. Your body isn't. Adaptation kicks in, plateaus happen, breaks are smart. Plan with a buffer.

Science

Scientific background

Rule of thumb: 1 kg of body fat ≈ 7,700 kcal. A 550 kcal/day deficit equals 0.5 kg/week on paper.

In practice, energy expenditure drops across a diet (adaptive thermogenesis, lower NEAT). The real loss rate flattens out.

Diet breaks of 1–2 weeks at maintenance can stabilise adherence and hormones without meaningfully slowing fat loss (Byrne et al. 2018).

Examples

Practical examples

85 → 78 kg @ 0.5 kg/week

≈ 14 weeks (~3.2 months). Required deficit ~550 kcal/day.

95 → 80 kg @ 0.75 kg/week

≈ 20 weeks (~4.6 months). Deficit ~825 kcal/day — watch energy and sleep closely.

Avoid these

Common mistakes

01Linear expectations. You won't lose the target amount each week.
02Picking an aggressive pace, then quitting early.
03No strength training in a deficit — lean mass suffers.
04Day-to-day comparisons instead of a 7-day average.

Recommendations

Further recommendations

01Pick 0.5 kg/week as default; go faster only with good reason.
02Plan diet breaks when the phase exceeds 8 weeks.
03Track weight as a 7-day average.
04Only adjust calories when the average stalls for 2 weeks.

FAQ

Frequently asked questions

Is the target date exact?: It's an estimate. Plan 10–20 % buffer and accept that your body has phases.
What pace is healthy?: 0.5–1.0 % of body weight per week. For most people, 0.5 kg/week is the ideal anchor.
Should I plan diet breaks?: Yes for phases longer than 8 weeks — 1–2 weeks at maintenance help mentally and hormonally.
What if I plateau?: Wait 2 weeks. Then either add steps or drop calories by 100 — not both at once.

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Knowledge Hub

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