Romanian Deadlift 1RM from 8 Reps — Epley and Brzycki Estimate

If you can romanian deadlift 100 kg for 8 reps, your estimated one-rep max is 125.4 kg — the average of the Epley estimate (126.7 kg) and the Brzycki estimate (124.1 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 Romanian Deadlift works the hamstrings and glutes, and it is a barbell lift. An intermediate lifter often Romanian-deadlifts around 1.3 times bodyweight, roughly 60 to 70 percent of a conventional deadlift max. The worked example below uses a 8-rep set with 100 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 8 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 100 kg for 8 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 romanian deadlift — 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 100 kg × 8 reps on the romanian deadlift:

  • Epley: 100 × (1 + 8 ÷ 30) = 100 × 1.3 = 126.7 kg
  • Brzycki: 100 × 36 ÷ (37 − 8) = 100 × 36 ÷ 29 = 124.1 kg
  • Average of the two: (126.7 + 124.1) ÷ 2 = 125.4 kg (276 lb)

The two formulas differ by 2.5 kg on this set. Sets of 8 reps are still a reliable basis for an estimate. At 8 reps the two formulas differ by 2.0 percent, which is a normal spread — the formulas were fitted to different groups of lifters, and they diverge slowly as the rep count rises. The average of the two is a sensible working estimate, and it is the number to base your training percentages on for the next four to six weeks. A 8-rep set is a good compromise between accuracy and safety: heavy enough to be informative, light enough that the test itself is not the workout.

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 8 reps with two more reps left in the tank will underestimate your max, because the formulas assume those 8 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 125.4 kg romanian deadlift 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 125.4 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% 62.7 kg 138 lb
55% 69.0 kg 152 lb
60% 75.2 kg 166 lb
65% 81.5 kg 180 lb
70% 87.8 kg 194 lb
75% 94.1 kg 207 lb
80% 100.3 kg 221 lb
85% 106.6 kg 235 lb
90% 112.9 kg 249 lb
95% 119.1 kg 263 lb
100% 125.4 kg 276 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 romanian deadlift, that is 100.3 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 87.8 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 125.4 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)
1 121.4 kg 268 lb
2 117.6 kg 259 lb
3 114.0 kg 251 lb
5 107.5 kg 237 lb
6 104.5 kg 230 lb
8 99.0 kg 218 lb
10 94.1 kg 207 lb
12 89.6 kg 197 lb
15 83.6 kg 184 lb
20 75.2 kg 166 lb

The row for 8 reps reads 99.0 kg, which sits within a kilogram or two of the 100 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 125.4 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 with a flat back for two sessions in a row. Train the Romanian deadlift once or twice a week, usually after squats or deadlifts, and progress the hinge slowly — the hamstrings respond to patient loading, and a strained hamstring costs weeks.

Warm up properly before any heavy set. For a Romanian deadlift session, that means a few light hinges with an empty bar or a light kettlebell, 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 8-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 romanian deadlift stresses the hamstrings and glutes, 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 romanian deadlift

The Romanian deadlift starts from the top — the bar is unracked or deadlifted up, then hinged back with soft knees while the bar slides down the thighs to about mid-shin, the hamstrings stretch, and the hips drive forward to stand. The standard that matters most is that it is a hinge, not a squat: the knees bend only slightly, the back stays flat, and the depth is set by hamstring flexibility, not by how low the bar can go. A set only counts if every rep keeps a flat back, the bar stays close to the legs, and the bottom position is the same on every rep.

The most common errors are bending the knees so far the lift becomes a squat, rounding the lower back to reach lower, letting the bar drift away from the legs, and overextending the lower back at the top. Each of these either shortens the hamstring stretch or adds risk, and none of them should count toward an estimate.

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 romanian deadlift 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 romanian deadlift 1RM if I lift 100 kg for 8 reps?

Using the worked example on this page: Epley gives 126.7 kg and Brzycki gives 124.1 kg, so the averaged estimate is 125.4 kg. That figure assumes the 8-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 — 2.5 kg here — is a warning sign rather than a detail to average away.

How accurate is a 1RM estimated from 8 reps?

Reliable enough to programme from. From sets of ten reps or fewer, Epley and Brzycki usually agree within a few percent, and the average is a sensible working estimate. It is still an estimate with error bars of several kilograms either way, so treat the training percentages as a guide and adjust by feel on the day — if 80 percent feels like 90 percent, trust the feeling, not the table.

How low should the bar go on a Romanian deadlift?

To about mid-shin, or to wherever your hamstrings stop you while your back stays flat — whichever comes first. Depth is set by your flexibility, not by a target height, and forcing the bar lower by rounding your back is how hamstrings and lower backs get hurt. Keep the bar close to your legs and the knees only slightly bent on every rep.

What weight should I train with for strength on the romanian deadlift?

Strength work is usually 85–95% of your estimated max. For a 125.4 kg max, that is 106.6 kg to 119.1 kg, for sets of 1–5 reps with three to five minutes of rest. For muscle growth, use 65–85% (81.5–106.6 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 romanian deadlift 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.