The plank test measures core endurance by timing how long you can hold a forearm plank with proper form. This calculator scores your hold time against age and gender fitness norms.
Score Your Plank Test
How to Use the Plank Test Calculator
Perform a forearm plank (elbows under shoulders, body straight, hips level) until you break form. Record your time and enter it above for a rating.
Plank Form Standards
Elbows directly under shoulders. Forearms flat on the ground. Body in a straight line from head to heels. Hips neither sagging nor raised. Core engaged. End the test when hips sag, hands leave the ground, or you can no longer maintain position.
Frequently Asked Questions
Is this plank test calculator free?
Yes, completely free with no signup required.
How long should you be able to hold a plank?
For a healthy adult aged 20–29: less than 30 seconds is poor; 30–60 seconds is below average; 60–90 seconds is average; 90–120 seconds is above average; 2+ minutes is excellent. Standards are similar across genders when normalized.
What muscles does a plank work?
The plank primarily works the transverse abdominis (deep core), rectus abdominis, obliques, glutes, and shoulder stabilizers. It is considered one of the most effective core exercises because it trains isometric strength in a functional position.
Is a forearm plank or straight-arm plank better?
Forearm planks focus more on the core; straight-arm planks add more shoulder activation. Both are effective. For standardized testing, forearm planks are more common and allow longer holds by reducing shoulder fatigue.
How do I improve my plank time?
Practice planks daily or every other day. Work up in 5–10 second increments per session. Supplement with hollow body holds, dead bugs, and anti-rotation exercises. Most people can double their plank time in 4–6 weeks with consistent training.