Seated Leg Curl vs Leg Extension Strength Standards
Compare your seated leg curl and leg extension against strength standards for your sex and bodyweight. Enter one recent set of 1–12 reps for each lift to see your estimated one-rep maxes, strength levels, next targets, and which lift you should prioritize.
Enter the displayed bilateral machine or stack weight separately for the seated leg curl and leg extension. Use a strict, repeatable seated leg curl set that follows the canonical setup, range, and lockout rules and a strict, repeatable leg extension set that follows the canonical setup, range, and lockout rules. You can enter either lift in pounds or kilograms. Each lift is compared with its own standards, so the heavier lift is not automatically the stronger one.
Seated Leg Curl vs Leg Extension Strength Standards by Bodyweight
Use these tables to compare the estimated one-rep max required for the seated leg curl and leg extension to reach the same strength level at each listed bodyweight. They show the targets used by the calculator—not a required difference between your seated leg curl and leg extension.
Choose the men’s or women’s table, find your bodyweight or the closest listed row, then read across to Novice, Intermediate, Advanced, or Elite. Every entry shows Seated Leg Curl / Leg Extension, with pounds first and kilograms underneath. For a result based on your exact bodyweight and recent sets, use the calculator above; you do not need to test either true one-rep max.
Men’s Seated Leg Curl vs Leg Extension Standards
How to read the table: The first number is Seated Leg Curl; the second is Leg Extension. Each number is the lowest estimated one-rep max needed to reach that strength level. Scroll horizontally on smaller screens.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 120 lb 54.4 kg | 39 / 49 lb 17.7 / 22.2 kg | 64 / 77 lb 29 / 34.9 kg | 95 / 109 lb 43.1 / 49.4 kg | 126 / 143 lb 57.2 / 64.9 kg |
| 130 lb 59 kg | 41 / 52 lb 18.6 / 23.6 kg | 68 / 82 lb 30.8 / 37.2 kg | 100 / 115 lb 45.4 / 52.2 kg | 133 / 151 lb 60.3 / 68.5 kg |
| 140 lb 63.5 kg | 43 / 55 lb 19.5 / 24.9 kg | 71 / 86 lb 32.2 / 39 kg | 105 / 121 lb 47.6 / 54.9 kg | 140 / 158 lb 63.5 / 71.7 kg |
| 150 lb 68 kg | 45 / 57 lb 20.4 / 25.9 kg | 74 / 90 lb 33.6 / 40.8 kg | 110 / 126 lb 49.9 / 57.2 kg | 146 / 166 lb 66.2 / 75.3 kg |
| 160 lb 72.6 kg | 47 / 60 lb 21.3 / 27.2 kg | 78 / 94 lb 35.4 / 42.6 kg | 115 / 132 lb 52.2 / 59.9 kg | 152 / 173 lb 68.9 / 78.5 kg |
| 170 lb 77.1 kg | 49 / 62 lb 22.2 / 28.1 kg | 81 / 97 lb 36.7 / 44 kg | 120 / 137 lb 54.4 / 62.1 kg | 159 / 180 lb 72.1 / 81.6 kg |
| 180 lb 81.6 kg | 51 / 65 lb 23.1 / 29.5 kg | 84 / 101 lb 38.1 / 45.8 kg | 124 / 143 lb 56.2 / 64.9 kg | 165 / 187 lb 74.8 / 84.8 kg |
| 190 lb 86.2 kg | 53 / 67 lb 24 / 30.4 kg | 87 / 105 lb 39.5 / 47.6 kg | 129 / 148 lb 58.5 / 67.1 kg | 171 / 194 lb 77.6 / 88 kg |
| 200 lb 90.7 kg | 55 / 69 lb 24.9 / 31.3 kg | 90 / 109 lb 40.8 / 49.4 kg | 133 / 153 lb 60.3 / 69.4 kg | 177 / 201 lb 80.3 / 91.2 kg |
| 210 lb 95.3 kg | 57 / 72 lb 25.9 / 32.7 kg | 93 / 112 lb 42.2 / 50.8 kg | 138 / 158 lb 62.6 / 71.7 kg | 183 / 207 lb 83 / 93.9 kg |
| 220 lb 99.8 kg | 58 / 74 lb 26.3 / 33.6 kg | 96 / 116 lb 43.5 / 52.6 kg | 142 / 163 lb 64.4 / 73.9 kg | 189 / 214 lb 85.7 / 97.1 kg |
| 230 lb 104.3 kg | 60 / 76 lb 27.2 / 34.5 kg | 99 / 119 lb 44.9 / 54 kg | 147 / 168 lb 66.7 / 76.2 kg | 194 / 220 lb 88 / 99.8 kg |
| 240 lb 108.9 kg | 62 / 78 lb 28.1 / 35.4 kg | 102 / 123 lb 46.3 / 55.8 kg | 151 / 173 lb 68.5 / 78.5 kg | 200 / 227 lb 90.7 / 103 kg |
| 250 lb 113.4 kg | 64 / 80 lb 29 / 36.3 kg | 104 / 126 lb 47.2 / 57.2 kg | 155 / 178 lb 70.3 / 80.7 kg | 205 / 233 lb 93 / 105.7 kg |
| 260 lb 117.9 kg | 65 / 83 lb 29.5 / 37.6 kg | 107 / 129 lb 48.5 / 58.5 kg | 159 / 182 lb 72.1 / 82.6 kg | 211 / 239 lb 95.7 / 108.4 kg |
| 270 lb 122.5 kg | 67 / 85 lb 30.4 / 38.6 kg | 110 / 133 lb 49.9 / 60.3 kg | 163 / 187 lb 73.9 / 84.8 kg | 216 / 245 lb 98 / 111.1 kg |
| 280 lb 127 kg | 69 / 87 lb 31.3 / 39.5 kg | 113 / 136 lb 51.3 / 61.7 kg | 167 / 192 lb 75.7 / 87.1 kg | 221 / 251 lb 100.2 / 113.9 kg |
| 290 lb 131.5 kg | 70 / 89 lb 31.8 / 40.4 kg | 115 / 139 lb 52.2 / 63 kg | 171 / 196 lb 77.6 / 88.9 kg | 227 / 257 lb 103 / 116.6 kg |
| 300 lb 136.1 kg | 72 / 91 lb 32.7 / 41.3 kg | 118 / 142 lb 53.5 / 64.4 kg | 175 / 201 lb 79.4 / 91.2 kg | 232 / 263 lb 105.2 / 119.3 kg |
Women’s Seated Leg Curl vs Leg Extension Standards
How to read the table: The first number is Seated Leg Curl; the second is Leg Extension. Each number is the lowest estimated one-rep max needed to reach that strength level. Scroll horizontally on smaller screens.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 100 lb 45.4 kg | 23 / 29 lb 10.4 / 13.2 kg | 39 / 46 lb 17.7 / 20.9 kg | 60 / 69 lb 27.2 / 31.3 kg | 80 / 89 lb 36.3 / 40.4 kg |
| 110 lb 49.9 kg | 24 / 31 lb 10.9 / 14.1 kg | 41 / 49 lb 18.6 / 22.2 kg | 63 / 73 lb 28.6 / 33.1 kg | 85 / 95 lb 38.6 / 43.1 kg |
| 120 lb 54.4 kg | 26 / 33 lb 11.8 / 15 kg | 44 / 52 lb 20 / 23.6 kg | 67 / 78 lb 30.4 / 35.4 kg | 90 / 101 lb 40.8 / 45.8 kg |
| 130 lb 59 kg | 27 / 35 lb 12.2 / 15.9 kg | 46 / 55 lb 20.9 / 24.9 kg | 71 / 82 lb 32.2 / 37.2 kg | 95 / 106 lb 43.1 / 48.1 kg |
| 140 lb 63.5 kg | 29 / 36 lb 13.2 / 16.3 kg | 49 / 57 lb 22.2 / 25.9 kg | 74 / 86 lb 33.6 / 39 kg | 100 / 112 lb 45.4 / 50.8 kg |
| 150 lb 68 kg | 30 / 38 lb 13.6 / 17.2 kg | 51 / 60 lb 23.1 / 27.2 kg | 78 / 90 lb 35.4 / 40.8 kg | 105 / 117 lb 47.6 / 53.1 kg |
| 160 lb 72.6 kg | 31 / 40 lb 14.1 / 18.1 kg | 53 / 63 lb 24 / 28.6 kg | 81 / 94 lb 36.7 / 42.6 kg | 110 / 122 lb 49.9 / 55.3 kg |
| 170 lb 77.1 kg | 33 / 41 lb 15 / 18.6 kg | 55 / 65 lb 24.9 / 29.5 kg | 85 / 98 lb 38.6 / 44.5 kg | 114 / 127 lb 51.7 / 57.6 kg |
| 180 lb 81.6 kg | 34 / 43 lb 15.4 / 19.5 kg | 58 / 68 lb 26.3 / 30.8 kg | 88 / 102 lb 39.9 / 46.3 kg | 119 / 132 lb 54 / 59.9 kg |
| 190 lb 86.2 kg | 35 / 44 lb 15.9 / 20 kg | 60 / 70 lb 27.2 / 31.8 kg | 91 / 105 lb 41.3 / 47.6 kg | 123 / 137 lb 55.8 / 62.1 kg |
| 200 lb 90.7 kg | 36 / 46 lb 16.3 / 20.9 kg | 62 / 73 lb 28.1 / 33.1 kg | 94 / 109 lb 42.6 / 49.4 kg | 127 / 142 lb 57.6 / 64.4 kg |
| 210 lb 95.3 kg | 38 / 48 lb 17.2 / 21.8 kg | 64 / 75 lb 29 / 34 kg | 98 / 113 lb 44.5 / 51.3 kg | 131 / 146 lb 59.4 / 66.2 kg |
| 220 lb 99.8 kg | 39 / 49 lb 17.7 / 22.2 kg | 66 / 77 lb 29.9 / 34.9 kg | 101 / 116 lb 45.8 / 52.6 kg | 136 / 151 lb 61.7 / 68.5 kg |
| 230 lb 104.3 kg | 40 / 51 lb 18.1 / 23.1 kg | 68 / 80 lb 30.8 / 36.3 kg | 104 / 120 lb 47.2 / 54.4 kg | 140 / 156 lb 63.5 / 70.8 kg |
| 240 lb 108.9 kg | 41 / 52 lb 18.6 / 23.6 kg | 70 / 82 lb 31.8 / 37.2 kg | 107 / 123 lb 48.5 / 55.8 kg | 144 / 160 lb 65.3 / 72.6 kg |
How Your Seated Leg Curl vs Leg Extension Result Is Calculated
The calculator estimates each max, rates it against the standards for that exercise and bodyweight, then compares the two ratings. Here is the complete process.
1. Estimate a one-rep max from each set
For one rep, it uses the weight entered. For 2–12 reps, it runs both formulas and keeps the lower, less aggressive estimate.
- Epley: weight × (1 + reps ÷ 30)
- Brzycki: weight × 36 ÷ (37 − reps)
A published back-squat study supports estimated-max prediction under its study conditions. It does not independently validate every exercise or population used by this comparison. Estimates are more dependable from clean, difficult, lower-rep sets. See the Back-squat formula validation study and Published discussion of back-squat one-rep-max prediction research.
2. Find the seated leg curl strength level
The standards use the sex-specific targets from the individual Seated Leg Curl tool. Targets begin at 190 lb for men and 150 lb for women, then adjust to your exact bodyweight: reference target × (user bodyweight ÷ reference bodyweight) to the two-thirds power.
The target rises more slowly than bodyweight so heavier lifters are expected to lift more without requiring strength to increase pound for pound.
3. Find the leg extension strength level
The standards use the sex-specific targets from the individual Leg Extension tool. Targets begin at 190 lb for men and 150 lb for women, then adjust to your exact bodyweight: reference target × (user bodyweight ÷ reference bodyweight) to the two-thirds power.
The target rises more slowly than bodyweight so heavier lifters are expected to lift more without requiring strength to increase pound for pound.
4. Compare the two results
Each max receives a level from Beginner through Elite. The lower-level lift is the priority. If the levels match, a priority appears only when one lift is at least 10 points farther from its next level. Otherwise, the result is Balanced.
The result shows which lift ranks lower, not why. Technique, fatigue, training history, and set quality can affect it. Age range is recorded anonymously but does not change the standards.
| Stage | What happens |
|---|---|
| Estimate each max | Use the entered weight for 1 rep; for 2–12 reps, keep the lower formula result. |
| Rate the seated leg curl | Adjust seated leg curl targets to exact bodyweight with the two-thirds rule. |
| Rate the leg extension | Adjust leg extension targets to exact bodyweight with the two-thirds rule. |
| Compare different levels | Name the lower-level lift as the priority. |
| Compare matching levels | Use Balanced unless the difference in progress toward the next level reaches 10 points. |
Use the calculator above to see both estimated maxes, strength levels, the priority or Balanced result, and both next-level targets.
How Men’s Seated Leg Curl and Leg Extension Standards Differ
How to read both charts: Choose a strength level, find bodyweight along the bottom, and follow that level’s line. Zero means the two standards are equal. Above zero means the leg extension standard is higher; below zero means the seated leg curl standard is higher. On a phone, swipe the chart left and right to inspect the full-size lines and labels. The tables provide the exact pounds and kilograms.
What the men’s data shows:
The standards come closest at 120 lb.
Novice, Intermediate, Advanced, and Elite at every displayed bodyweight.
7.7 → 14.1 kg from 120 to 300 lb bodyweight.
How to read the table: Every number is the leg extension standard minus the seated leg curl standard. A plus sign means the leg extension standard is higher. A minus sign means the seated leg curl standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 120 lb 54.4 kg | +10 lb +4.5 kg | +13 lb +5.9 kg | +14 lb +6.3 kg | +17 lb +7.7 kg |
| 130 lb 59 kg | +11 lb +5 kg | +14 lb +6.4 kg | +15 lb +6.8 kg | +18 lb +8.2 kg |
| 140 lb 63.5 kg | +12 lb +5.4 kg | +15 lb +6.8 kg | +16 lb +7.3 kg | +18 lb +8.2 kg |
| 150 lb 68 kg | +12 lb +5.5 kg | +16 lb +7.2 kg | +16 lb +7.3 kg | +20 lb +9.1 kg |
| 160 lb 72.6 kg | +13 lb +5.9 kg | +16 lb +7.2 kg | +17 lb +7.7 kg | +21 lb +9.6 kg |
| 170 lb 77.1 kg | +13 lb +5.9 kg | +16 lb +7.3 kg | +17 lb +7.7 kg | +21 lb +9.5 kg |
| 180 lb 81.6 kg | +14 lb +6.4 kg | +17 lb +7.7 kg | +19 lb +8.7 kg | +22 lb +10 kg |
| 190 lb 86.2 kg | +14 lb +6.4 kg | +18 lb +8.1 kg | +19 lb +8.6 kg | +23 lb +10.4 kg |
| 200 lb 90.7 kg | +14 lb +6.4 kg | +19 lb +8.6 kg | +20 lb +9.1 kg | +24 lb +10.9 kg |
| 210 lb 95.3 kg | +15 lb +6.8 kg | +19 lb +8.6 kg | +20 lb +9.1 kg | +24 lb +10.9 kg |
| 220 lb 99.8 kg | +16 lb +7.3 kg | +20 lb +9.1 kg | +21 lb +9.5 kg | +25 lb +11.4 kg |
| 230 lb 104.3 kg | +16 lb +7.3 kg | +20 lb +9.1 kg | +21 lb +9.5 kg | +26 lb +11.8 kg |
| 240 lb 108.9 kg | +16 lb +7.3 kg | +21 lb +9.5 kg | +22 lb +10 kg | +27 lb +12.3 kg |
| 250 lb 113.4 kg | +16 lb +7.3 kg | +22 lb +10 kg | +23 lb +10.4 kg | +28 lb +12.7 kg |
| 260 lb 117.9 kg | +18 lb +8.1 kg | +22 lb +10 kg | +23 lb +10.5 kg | +28 lb +12.7 kg |
| 270 lb 122.5 kg | +18 lb +8.2 kg | +23 lb +10.4 kg | +24 lb +10.9 kg | +29 lb +13.1 kg |
| 280 lb 127 kg | +18 lb +8.2 kg | +23 lb +10.4 kg | +25 lb +11.4 kg | +30 lb +13.7 kg |
| 290 lb 131.5 kg | +19 lb +8.6 kg | +24 lb +10.8 kg | +25 lb +11.3 kg | +30 lb +13.6 kg |
| 300 lb 136.1 kg | +19 lb +8.6 kg | +24 lb +10.9 kg | +26 lb +11.8 kg | +31 lb +14.1 kg |
How Women’s Seated Leg Curl and Leg Extension Standards Differ
What the women’s data shows:
The standards come closest at 100 lb.
Novice, Intermediate, Advanced, and Elite at every displayed bodyweight.
4.1 → 7.3 kg from 100 to 240 lb bodyweight.
How to read the table: Every number is the leg extension standard minus the seated leg curl standard. A plus sign means the leg extension standard is higher. A minus sign means the seated leg curl standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 100 lb 45.4 kg | +6 lb +2.8 kg | +7 lb +3.2 kg | +9 lb +4.1 kg | +9 lb +4.1 kg |
| 110 lb 49.9 kg | +7 lb +3.2 kg | +8 lb +3.6 kg | +10 lb +4.5 kg | +10 lb +4.5 kg |
| 120 lb 54.4 kg | +7 lb +3.2 kg | +8 lb +3.6 kg | +11 lb +5 kg | +11 lb +5 kg |
| 130 lb 59 kg | +8 lb +3.7 kg | +9 lb +4 kg | +11 lb +5 kg | +11 lb +5 kg |
| 140 lb 63.5 kg | +7 lb +3.1 kg | +8 lb +3.7 kg | +12 lb +5.4 kg | +12 lb +5.4 kg |
| 150 lb 68 kg | +8 lb +3.6 kg | +9 lb +4.1 kg | +12 lb +5.4 kg | +12 lb +5.5 kg |
| 160 lb 72.6 kg | +9 lb +4 kg | +10 lb +4.6 kg | +13 lb +5.9 kg | +12 lb +5.4 kg |
| 170 lb 77.1 kg | +8 lb +3.6 kg | +10 lb +4.6 kg | +13 lb +5.9 kg | +13 lb +5.9 kg |
| 180 lb 81.6 kg | +9 lb +4.1 kg | +10 lb +4.5 kg | +14 lb +6.4 kg | +13 lb +5.9 kg |
| 190 lb 86.2 kg | +9 lb +4.1 kg | +10 lb +4.6 kg | +14 lb +6.3 kg | +14 lb +6.3 kg |
| 200 lb 90.7 kg | +10 lb +4.6 kg | +11 lb +5 kg | +15 lb +6.8 kg | +15 lb +6.8 kg |
| 210 lb 95.3 kg | +10 lb +4.6 kg | +11 lb +5 kg | +15 lb +6.8 kg | +15 lb +6.8 kg |
| 220 lb 99.8 kg | +10 lb +4.5 kg | +11 lb +5 kg | +15 lb +6.8 kg | +15 lb +6.8 kg |
| 230 lb 104.3 kg | +11 lb +5 kg | +12 lb +5.5 kg | +16 lb +7.2 kg | +16 lb +7.3 kg |
| 240 lb 108.9 kg | +11 lb +5 kg | +12 lb +5.4 kg | +16 lb +7.3 kg | +16 lb +7.3 kg |
Seated Leg Curl and Leg Extension Exercises Used by This Calculator
This calculator uses a strict seated leg curl and a strict leg extension. Use strict bilateral seated-machine reps under each tool’s seat, pad, start, range, and finish rules. Do not substitute unilateral reps, lying or standing curls, cable variations, partial reps, stack bounce, hip lift, kicking, or assisted reps.
Use a strict, repeatable Seated Leg Curl
Selected or loaded machine resistance is used Enter total bilateral load, not per-leg load Do not add bodyweight to the entered load Strict seated bilateral machine leg curl Thigh restraint and lower-leg pad stay consistent Back, hips, pelvis, thighs, seat, and pad position stay stable Enter displayed machine or stack weight. Keep the same equipment and setup when retesting.
Use a strict, repeatable Leg Extension
the selected or added machine resistance for both legs together strict two-leg machine leg extension reps extend both knees from the same controlled seated start to a repeatable near-straight finish, then return without kicking, hip lift, pad bounce, seat slide, or shortened range Consistent setup, range, and finish quality across the entered set No substituted exercise or assisted reps Enter displayed machine or stack weight. Keep the same equipment and setup when retesting.
Enter one recent Seated Leg Curl set and one recent Leg Extension set
Enter each machine’s displayed bilateral resistance and a whole number from 1 to 12 strict repetitions. Pounds and kilograms can be mixed. Keep each machine and setup consistent.
Related Tools
- Seated Leg Curl — View the individual Seated Leg Curl standards and next strength-level target.
- Leg Extension — View the individual Leg Extension standards and next strength-level target.
- Lying Leg Curl — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.
- Leg Press (45° Sled) — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.
- Machine Hack Squat — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.