Plank Time Norm Calculator

Work out plank time norm instantly with clear inputs, formula shown and shareable results.

About Plank Time Norm Calculator

Plank endurance norms sit near 110 seconds for men and 95 for women at 30, declining roughly 1.2 seconds a year. A 90 second hold at 35 is about 88% of norm - average. Holding beyond about two minutes adds little; progressing to loaded or single-arm variations trains the same quality more efficiently.

Formulas

Age-adjusted norm

expected = base - 1.2 x (age - 30) seconds

Score

percentage = hold time / expected x 100

Worked example

With the default values below, Plank Time Norm Calculator returns Score Against Age Norm of 86.5%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Plank hold timeminimum 0 s: 90 s
Ageaccepts 10–100 years: 35 years
Sexone of Male, Female: Male

Results

Score Against Age Norm: 86.5%
Expected Hold For Your Age: 104.0 s
Rating: Average
Hold Time As m:ss: 1:30

Step by step

1Values used
2Age-adjusted norm
3Score
4Score Against Age Norm= 86.5
5Expected Hold For Your Age= 104.0 s
6Rating= Average
7Hold Time As m:ss= 1:30

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
This is an estimate from population-average equations, not a medical or diagnostic assessment. Individual results vary with genetics, training history and technique. Seek advice from a qualified coach or clinician before making significant changes to training.
This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

This is an estimate from population-average equations, not a medical or diagnostic assessment. Individual results vary with genetics, training history and technique. Seek advice from a qualified coach or clinician before making significant changes to training.

Frequently Asked Questions

Is a longer plank always better?

No. Past two minutes the limiting factor becomes discomfort rather than trunk strength, so added load or instability trains more.

What breaks a valid plank?

Hips sagging or rising out of line, shoulders drifting behind the elbows, or holding the breath. Stop the clock when alignment fails.