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Bicep curl max calculator

Enter the weight of a recent strict curl set, the reps you completed and how many more you could have done. The calculator estimates your curl one-rep max and turns it into weights for sets of 6 to 15, the range curls are usually trained in.

Exercise
Unit
Reps in reserve

How many more you could have done. 0 means none.

Example result

Estimated curl 1RM

39kg

Brzycki, for comparison

40kg

30 kg × 8 with 2 in reserve counts as 10 reps to failure.

Your rep maxes
  • 38 kg2RM
  • 37 kg3RM
  • 34 kg5RM
  • 32 kg8RM
  • 30 kg10RM
Working loads from your estimated max, rounded to 1 kg
GoalSets × repsRIRLoad
Heavier sixes3 × 6232 kg
Muscle-building eights3 × 8230 kg
Twelves3 × 12128 kg
High-rep fifteens2 × 15126 kg
Build a curl session from this set

Curl max examples

Curls are where body English, small plates and fixed bars quietly change the number. Each example is a straight-bar set from a different lifter.

  • Example 1

    Ten reps, three of them swung

    A lifter who got 80 lb for 10 on a straight bar, but the last three needed a hip swing. Only 7 were strict.

    Exercise
    Barbell
    Weight lifted
    80 lb
    Reps completed
    7
    Reps in reserve
    0
    • Estimated curl 1RM96 lb

    Counting all 10 would put the max about 8 lb higher, and every working weight with it. Enter the strict reps, train at the eights weight, and the swing has nowhere to hide.

    Build a curl session from this set Open with these numbers

  • Example 2

    A woman's first max, in kilograms

    A woman curling 20 kg, bar included, on a plate-loaded straight bar for 8 reps with 2 left, with 0.5 kg plates in her gym.

    Exercise
    Barbell
    Weight lifted
    20 kg
    Reps completed
    8
    Reps in reserve
    2
    • Estimated curl 1RM26 kg

    Her working weights sit 1 kg apart, which her small plates can load. Without them she'd be stuck making 2.5 kg jumps, over 10% of her eights weight, so she would add reps first instead.

    Build a curl session from this set Open with these numbers

  • Example 3

    A heavy six before arm day

    An experienced lifter who curled 90 lb on an EZ bar for 6 strict reps with 1 left.

    Exercise
    EZ bar
    Weight lifted
    90 lb
    Reps completed
    6
    Reps in reserve
    1
    • Estimated curl 1RM108 lb

    A heavy, strict six is the cleanest curl test there is. He doesn't need to go heavier than this: the sixes and eights in the table carry his strength work, the twelves his volume.

    Build a curl session from this set Open with these numbers

  • Example 4

    A light set of 10

    A beginner who curled a pair of 10 kg dumbbells for 10 reps with about 2 left.

    Exercise
    Dumbbells, per arm
    Weight lifted
    10 kg
    Reps completed
    10
    Reps in reserve
    2
    • Estimated curl 1RM~13.5 kg

    Twelve reps to failure is past where a max estimate holds up, so the result is marked rough. Next session, take a weight you can curl 6 to 8 times with 2 left and run it again.

    Build a curl session from this set Open with these numbers

Barbell, EZ bar or dumbbells: whose max is it?

A curl max belongs to the implement you tested it on. A straight bar keeps your palms fully up, an EZ bar tilts them in, and dumbbells let each arm work alone and turn the palm as it lifts. Each changes the weight you can move, so a max from one doesn't transfer cleanly to another.

For a barbell or EZ bar, enter the total weight, bar included. For dumbbells, enter one dumbbell and read the result per arm. The dumbbell to barbell calculator is built for the pressing version of that question.

Cheat reps and your curl max

A rep where your hips swing, your back leans or your elbows drift forward isn't a biceps rep at that weight. It feels like a max, and it puts every working weight above what your arms can do strictly.

Count only reps where your upper arms stay at your sides and your arms straighten at the bottom. For reps in reserve, count strict reps left, not how many more you could have heaved up. The RIR guide explains how to judge it.

Curl technique

The curl this calculator defaults to

Barbell Curl

Biceps

Both arms share one bar, so it's the curl where you can load the most and add weight in the smallest steps. That also makes it the easiest curl to cheat: strict form is what keeps the max honest.

How to do it

  1. Stand tall with your feet hip-width apart and hold the bar underhand, hands a little wider than your hips.
  2. Let the bar hang at your thighs with your arms straight and your elbows touching your sides.
  3. Curl the bar up in an arc by bending your elbows, upper arms still and wrists straight.
  4. Stop when your forearms are vertical and the bar is in front of your shoulders.
  5. Lower the bar under control until your arms are completely straight.

Cues

  • Elbows pinned to your ribs
  • Ribs down, no lean back
  • Straight arms at the bottom of every rep

Common mistakes

  • Leaning back and using the hips: if the bar only moves with a swing, it's too heavy for the rep target.
  • Half reps that never straighten the arms, which overstate what your biceps can do.

Full barbell curl guide

The wrist-friendly bar

EZ-Bar Curl

Biceps

The angled grip takes strain off the wrists and elbows, which is why many people curl heavier sets on it. Its max is its own, so log it separately from the straight bar.

How to do it

  1. Take the inner angled grips with your palms facing up and slightly in.
  2. Let the bar hang against your thighs with your arms straight and your elbows by your ribs.
  3. Bend at the elbows to bring the bar up until your forearms point roughly at the ceiling.
  4. Pause for a moment at the top without letting your elbows drift forward.
  5. Lower the bar for about two seconds until your arms are fully straight.

Cues

  • Elbows glued to your sides
  • Ribs down, no lean back
  • All the way down every rep

Common mistakes

  • Swinging the hips to get the bar moving: if the first inch needs a hip snap, the weight is too heavy.
  • Letting the elbows travel forward at the top, which turns the end of the curl into a front raise.

Full EZ-bar curl guide

One arm at a time

Dumbbell Curl

Biceps

Each arm lifts its own weight, so a weaker side can't lean on the stronger one. The result here is per arm, from the weight of one dumbbell.

How to do it

  1. Stand tall holding two dumbbells, arms straight at your sides, palms facing forward.
  2. Brace your stomach and pin your upper arms to your sides.
  3. Bend one elbow and bring the dumbbell toward your shoulder, palm turned up the whole way.
  4. Pause with your forearm vertical, then lower slowly until the arm is straight.
  5. Repeat with the other arm, or curl both together.

Cues

  • Elbows stay at your sides
  • Pinkie turns up
  • Slow on the way down

Common mistakes

  • Swinging your hips and back to get the weight up: take a lighter pair.
  • Stopping short of straight arms at the bottom.

Full dumbbell curl guide

Make it fit you

  • Test with 5 to 8 strict reps

    The estimate is built for sets up to 10 reps to failure, and a set of 5 to 8 with a couple left stays well inside that, without testing a single.

  • Round to the jumps you have

    Working weights round to 1 kg or 2.5 lb. If your gym's fixed bars or dumbbells go up in 5 kg or 5 lb, take the nearest one below and add reps until you can move up.

  • Train curls in higher reps

    The table runs from 6 to 15 reps. Moderate weights build muscle as well as heavy ones with less joint strain, so most of your sets belong in the eights and twelves.

  • Log each bar separately

    Keep separate numbers for the straight bar, EZ bar, dumbbells and cable. Mixing them makes it look like you got stronger or weaker when you only changed bars.

  • Add weight when the reps say so

    Move up when every set reaches the top of the range with reps to spare. The progressive overload calculator plans the jumps.

Questions

How do I calculate my curl max?

Curl a weight for 5 to 8 strict reps, note how many more strict reps you had left, and enter the weight, reps and reps in reserve above.

Is my dumbbell curl max per arm?

Yes, if you enter the weight of one dumbbell. It isn't half of a barbell curl max, so compare it only with other dumbbell curls.

Is an EZ bar curl max the same as a straight bar max?

Not exactly. The grip changes the lift, so test and log each bar on its own.

Should I test a one-rep max on curls?

There's little reason to. A hard set of 5 to 8 with an honest reps-in-reserve number gives the estimate without the strain of a single.

Is a 100 lb curl good?

It depends on your size and how long you've trained. The comparison that matters is your own strict curl max from a few months ago.

How many reps should I do for curls?

There's no single best number: a 2021 review found similar muscle growth across a wide range of loads and called moderate loads the most practical. Sets of 8 to 15 stopped 1 or 2 reps short of failure fit that, and the best workout for biceps builds them into a session.

Sources

Curl heavier without the guesswork

Log load, reps and RIR on every curl set and RIRLift keeps your estimated curl max current, then sets the next session's weight, rounded to a load you can actually put on.

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