Incline Bench Press 1RM from 20 Reps — Epley and Brzycki Estimate

If you can incline bench press 60 kg for 20 reps, your estimated one-rep max is 113.5 kg — the average of the Epley estimate (100.0 kg) and the Brzycki estimate (127.1 kg). That is the headline number, and the rest of this page shows exactly how it was calculated, what loads to train with at every percentage of it, and how far you should trust it.

The Incline Bench Press works the upper chest, shoulders and triceps, and it is a barbell lift. An intermediate lifter often incline-presses around 0.8 times bodyweight, and most lifters incline about 80 percent of what they flat bench. The worked example below uses a 20-rep set with 60 kg as the load — that is an assumption for illustration, not a prescription for you. Put your own weight and reps into the One Rep Max Calculator and the same two formulas will estimate your own max in seconds.

An estimated one-rep max matters because almost every serious strength programme is written in percentages of it. "Five sets of five at 80%" only means something if you know what 100% is, and testing a true one-rep max is risky, fatiguing and unnecessary for most lifters. A submaximal set of 20 reps gives you the number without the risk — provided you understand the limits of the formulas, which this page sets out honestly.

Use the one-rep-max calculator for your own numbers

The worked example on this page uses 60 kg for 20 reps. Your numbers will be different, and the calculator does the same maths with them. Use the One Rep Max Calculator for this lift, or the general One Rep Max Calculator for any lift, and you will get the Epley estimate, the Brzycki estimate, their average, and the full training-percentage table for your own max.

For comparison, here are the other one-rep-max pages for the incline bench press — the same two formulas applied to different rep counts:

The formulas, shown and cited

Two published formulas estimate a one-rep max from a submaximal set. Both are shown here with their sources, and both are worked through with this page's numbers.

Epley (Epley 1985): 1RM = weight × (1 + reps ÷ 30)

Brzycki (Brzycki 1993): 1RM = weight × 36 ÷ (37 − reps)

Worked through for 60 kg × 20 reps on the incline bench press:

  • Epley: 60 × (1 + 20 ÷ 30) = 60 × 1.7 = 100.0 kg
  • Brzycki: 60 × 36 ÷ (37 − 20) = 60 × 36 ÷ 17 = 127.1 kg
  • Average of the two: (100.0 + 127.1) ÷ 2 = 113.5 kg (250 lb)

The two formulas differ by 27.1 kg on this set. At 20 reps the formulas are outside their comfort zone, and you can see it in the gap: they differ by 23.8 percent here. A 20-rep set is an endurance test as much as a strength test — breathing, conditioning and mental toughness matter as much as maximal strength, and the formulas cannot separate those. Treat the average as a rough guide only, not a number to plan a strength block around. If you want a tighter estimate, re-test with a set of 5 to 8 reps; the 20-rep figure is most useful for setting endurance loads and for tracking whether your high-rep strength is improving over time.

Neither formula is magic. Both were fitted to real lifting data, and both assume the set was taken close to failure with good technique — a set of 20 reps with two more reps left in the tank will underestimate your max, because the formulas assume those 20 reps were hard. If you stopped well short of failure, add that to your interpretation: the estimate is a floor, not a ceiling. And if your technique broke down on the last rep, the set does not count for estimation purposes at all.

Training percentages for a 113.5 kg incline bench press max

Most programmes prescribe loads as a percentage of your one-rep max. The table below gives the load for every percentage from 50% to 100% of the 113.5 kg estimate, so you can read your working weights straight off it without doing the multiplication in your head between sets.

% of 1RM Load (kg) Load (lb)
50% 56.8 kg 125 lb
55% 62.4 kg 138 lb
60% 68.1 kg 150 lb
65% 73.8 kg 163 lb
70% 79.5 kg 175 lb
75% 85.1 kg 188 lb
80% 90.8 kg 200 lb
85% 96.5 kg 213 lb
90% 102.2 kg 225 lb
95% 107.9 kg 238 lb
100% 113.5 kg 250 lb

How those percentages are used in practice depends on the goal. Strength work lives at 85–95% of 1RM for sets of 1–5 reps, with long rests of three to five minutes. Hypertrophy work lives at 65–85% for sets of 6–12 reps, with rests of 60–120 seconds. Muscular endurance work lives at 50–65% for sets of 15 or more reps, with short rests. The same max produces all three training zones; what changes is the percentage and the rep count, not the lift.

A practical example: if your programme calls for five sets of five at 80% on the incline bench press, that is 90.8 kg for five reps, five times, with three minutes of rest between sets. If it calls for three sets of ten at 70%, that is 79.5 kg for ten reps, three times, with 90 seconds of rest. The table above is the only arithmetic you need; the programme supplies the sets, reps and rest.

What you can lift for other rep counts

If your estimated max is 113.5 kg, the table below gives the load you should be able to handle for each rep count, worked out from the Epley relationship between reps and percentage of maximum. Use it to pick weights for any set in your programme, not just the ones at your tested rep count.

Reps Estimated load (kg) Estimated load (lb)
1 109.9 kg 242 lb
2 106.4 kg 235 lb
3 103.2 kg 228 lb
5 97.3 kg 215 lb
6 94.6 kg 209 lb
8 89.6 kg 198 lb
10 85.1 kg 188 lb
12 81.1 kg 179 lb
15 75.7 kg 167 lb
20 68.1 kg 150 lb

The row for 20 reps reads 68.1 kg, which sits within a kilogram or two of the 60 kg used in the worked example — the small difference is because this table is built from the averaged estimate rather than from either formula alone. That is the honest way to read it: the table is a guide for choosing weights, and the right weight on the day is the one you can lift with good technique for the prescribed reps, not the number in the cell.

How to use the result, and how to progress safely

Use the 113.5 kg figure as a planning number, not as a weight to attempt tomorrow. The safest way to use an estimated max is to base your training percentages on it for four to six weeks, then re-test with a fresh submaximal set and update the estimate. If the new set gives a higher estimate, your training weights go up; if it gives the same number, you have maintained; if it gives a lower number, you may be under-recovered and need a lighter week.

Add 2.5 kg to the bar when you complete all prescribed sets and reps at a given weight for two sessions in a row. Train the incline press once or twice a week, usually after the flat bench on the same day, and keep the bench angle identical every session.

Warm up properly before any heavy set. For an incline session, that means the empty bar, then 50 percent of your working weight for a few reps, then 70 percent, then your working sets — never jumping straight from the warm-up to a heavy load. And never test a true one-rep max alone, without spotters or safety bars. The whole point of estimating from a 20-rep set is that you never have to find out what your true max is by attempting it.

Recovery is part of the programme, not a break from it. The incline bench press stresses the upper chest, shoulders and triceps, and those muscles need 48–72 hours before they are trained hard again. Sleep, food and rest days are where the strength is actually built; the training session is just the stimulus. A lifter who adds weight to the bar every week while sleeping five hours a night will stall and then regress, and no formula can fix that.

Technique standards for the incline bench press

The incline bench press is performed on a bench set to 30 to 45 degrees, with the bar lowered to the upper chest and pressed back up, using the same standards as the flat bench: touch the chest, no bounce, hips on the bench, feet on the floor. The standard that matters most is the bench angle, because a steeper bench shifts the work to the shoulders and lowers the weight you can handle. A set only counts for estimation if it is done at the same angle you will test at next time — record the angle, or the comparison between estimates is meaningless.

The most common errors are changing the bench angle between sessions, bouncing the bar off the upper chest, lifting the hips off the bench, and letting the elbows flare. Each of these inflates the rep count, and the angle change alone can move the estimate by several kilograms.

What the number does NOT tell you

An estimated one-rep max is a useful number with clear limits. First, it is an estimate, not a measurement. Your true max can only be found by attempting a maximum lift, and the estimate can be off by 5–10% in either direction even from a good set. That is why the percentage table above should be treated as a guide: if 80% feels like 90% on the day, trust the feeling, not the table.

Second, the formulas assume good technique. A incline bench press performed with a shortened range of motion or momentum will produce a higher rep count than a strict set, and the formulas will reward that with an inflated max. Compare estimates only between sets done the same way — same depth, same pause, same standard. A stricter set that gives a lower estimate is more useful than a sloppy set that gives a higher one.

Third, a one-rep max says nothing about your health, your body composition or your overall fitness. It measures one thing — the most weight you can lift once in this movement — and a big number in one lift does not imply a big number in another, let alone general health. It also says nothing about injury risk: a lifter with a large estimated max and poor technique is closer to an injury than a lifter with a modest max and excellent technique.

Finally, the formulas are population tools. They were fitted to groups of lifters, and individuals vary. Some lifters are naturally better at high reps than at singles, and the formulas will underestimate their max; others are the opposite, and the formulas will overestimate. Over time you will learn your own pattern — whether your true max tends to sit above or below the estimate — and you can adjust your training percentages accordingly.

Frequently asked questions

What is my incline bench press 1RM if I lift 60 kg for 20 reps?

Using the worked example on this page: Epley gives 100.0 kg and Brzycki gives 127.1 kg, so the averaged estimate is 113.5 kg. That figure assumes the 20-rep set was taken close to failure with good technique. For your own weight and rep count, use the One Rep Max Calculator.

Which formula is better, Epley or Brzycki?

Neither is clearly better in general — that is why this page averages them. Epley (1985) tends to give slightly higher estimates at higher rep counts, while Brzycki (1993) is often a little more conservative. From sets of ten reps or fewer the two usually agree within a few kilograms, and the average is a sensible compromise. Above ten reps both become less reliable, and the gap between them — 27.1 kg here — is a warning sign rather than a detail to average away.

Why is a 1RM estimated from 20 reps less reliable?

Because both formulas were fitted to low-rep data, and at 20 reps the set tests endurance and conditioning as much as maximal strength. Epley and Brzycki diverge sharply at high reps, so their average is a rough guide rather than a precise number. Use it to set endurance loads and to track high-rep progress, and re-test at 10 reps or fewer when you need a number to plan heavy training around.

Does the bench angle change my incline bench estimate?

Yes. A 30-degree bench lets you lift more than a 45-degree bench, because the steeper the bench, the more the shoulders do and the less the chest does. Record your angle and keep it identical every time you test, or the estimates will drift by several kilograms for no real reason.

What weight should I train with for strength on the incline bench press?

Strength work is usually 85–95% of your estimated max. For a 113.5 kg max, that is 96.5 kg to 107.9 kg, for sets of 1–5 reps with three to five minutes of rest. For muscle growth, use 65–85% (73.8–96.5 kg) for sets of 6–12 reps. The full percentage table above covers every step from 50% to 100%.

How often should I re-test my incline bench press max?

Every four to eight weeks is enough for most lifters. Testing more often wastes training time and adds fatigue without new information, because strength changes slowly. Re-test with the same rep count and the same technique standard as last time, so the two estimates are genuinely comparable, and update your training percentages from the new figure.

Related pages

Estimates only, not medical advice. Minimum safe intakes: 1,200 kcal/day women, 1,500 kcal/day men — consult a healthcare professional before a very-low-calorie diet.