One Rep Max for 400 lbs × 9 reps

One Rep Max Calculator

One Rep Max for

lifted for

reps

What is the one rep max for 400 lbs × 9 reps?

Answer

Lifting 400 lbs for 9 reps gives an estimated one rep max of
520 lbs

A set of 9 reps at 400 lbs is

76.9%

of your estimated one rep max

Note: this is an estimate, not a tested max. Rep-based formulas are closest at 2–6 reps and drift further apart as the set gets longer. Warm up and use a spotter before attempting a true single.

How to Calculate One Rep Max

Epley Formula: 1RM = weight × (1 + reps ÷ 30)

The Epley formula assumes that every extra repetition you can complete corresponds to roughly 3.33% more weight on the bar. Put your set into it:

400 × (1 + 9 ÷ 30)

=

400 × 1.3

=

520 lbs

Training Weights as a % of 1RM

Percentages of your estimated max of 520 lbs, the way most strength programmes prescribe load:

% of 1RMWorking Weight
95%494 lbs
90%468 lbs
85%442 lbs
80%416 lbs
75%390 lbs
70%364 lbs
65%338 lbs
60%312 lbs

Other One Rep Max Formulas

Published 1RM formulas disagree, and the gap widens with the rep count. This page answers with Epley; here is what the others give for 400 lbs × 9 reps:

FormulaEstimated 1RM
Epley520 lbs
Brzycki514.3 lbs
Lombardi498.3 lbs
O'Conner490 lbs
Wathan527.1 lbs
Lander517.7 lbs
Mayhew514.5 lbs

Related Calculations

See Also

One Rep Max Calculator

This calculator estimates your one-rep max (1RM) — the heaviest weight you could lift for a single repetition — from a set you have already completed. For example, it can help you find out what is the one rep max for 400 lbs × 9 reps? (The answer is: 520 lbs). Enter the weight you lifted (e.g. 400), pick pounds or kilograms, and enter how many reps you managed (e.g. 9).

One Rep Max Calculator

One Rep Max for

lifted for

reps

One Rep Max Table for 400 lbs

RepsOne Rep Max% of 1RM
2 reps426.7 lbs93.8%
3 reps440 lbs90.9%
4 reps453.3 lbs88.2%
5 reps466.7 lbs85.7%
6 reps480 lbs83.3%
7 reps493.3 lbs81.1%
8 reps506.7 lbs78.9%
9 reps520 lbs76.9%
10 reps533.3 lbs75%
11 reps546.7 lbs73.2%
12 reps560 lbs71.4%

FAQ

What is the one rep max for 400 lbs × 9 reps?

Lifting 400 lbs for 9 reps gives an estimated one rep max of 520 lbs

How much of my max is 400 lbs for 9 reps?

400 lbs for 9 reps works out at 76.9% of an estimated one rep max of 520 lbs.

What should I lift at 90% and 70% of that max?

90% of 520 lbs is 468 lbs and 70% is 364 lbs. Heavy strength work usually sits at 85–95%, while volume and technique work sits nearer 65–75%.

See Also