Leg Extension vs Barbell Hack Squat Strength Standards
Compare your leg extension and barbell hack squat against strength standards for your sex and bodyweight. Enter 1–12 reps for estimated one-rep maxes, strength levels, next targets, and priority.
Enter displayed bilateral machine resistance for the leg extension and total barbell weight for the barbell hack squat. Testing: a strict bilateral leg extension on one dedicated machine with stable hips and torso, a controlled flexed-knee start, near-straight finish, and controlled return; a free-weight barbell hack squat with the bar behind the legs, consistent depth, controlled descent, stable knees and torso, and full standing lockout. Pounds or kilograms. Heavier lift is not automatically the stronger one.
Leg Extension vs Barbell Hack Squat Strength Standards by Bodyweight
Use these tables to compare the estimated one-rep max required for the leg extension and barbell hack squat to reach the same strength level at each listed bodyweight. They show the targets used by the calculator—not a required difference between your leg extension and barbell hack squat.
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 Leg Extension / Barbell Hack Squat, 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 Leg Extension vs Barbell Hack Squat Standards
How to read the table: The first number is Leg Extension; the second is Barbell Hack Squat. 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 | 49 / 105 lb 22.2 / 47.6 kg | 77 / 147 lb 34.9 / 66.7 kg | 109 / 189 lb 49.4 / 85.7 kg | 143 / 231 lb 64.9 / 104.8 kg |
| 130 lb 59 kg | 52 / 111 lb 23.6 / 50.3 kg | 82 / 155 lb 37.2 / 70.3 kg | 115 / 200 lb 52.2 / 90.7 kg | 151 / 244 lb 68.5 / 110.7 kg |
| 140 lb 63.5 kg | 55 / 117 lb 24.9 / 53.1 kg | 86 / 163 lb 39 / 73.9 kg | 121 / 210 lb 54.9 / 95.3 kg | 158 / 256 lb 71.7 / 116.1 kg |
| 150 lb 68 kg | 57 / 122 lb 25.9 / 55.3 kg | 90 / 171 lb 40.8 / 77.6 kg | 126 / 220 lb 57.2 / 99.8 kg | 166 / 268 lb 75.3 / 121.6 kg |
| 160 lb 72.6 kg | 60 / 128 lb 27.2 / 58.1 kg | 94 / 178 lb 42.6 / 80.7 kg | 132 / 229 lb 59.9 / 103.9 kg | 173 / 280 lb 78.5 / 127 kg |
| 170 lb 77.1 kg | 62 / 133 lb 28.1 / 60.3 kg | 97 / 186 lb 44 / 84.4 kg | 137 / 239 lb 62.1 / 108.4 kg | 180 / 292 lb 81.6 / 132.4 kg |
| 180 lb 81.6 kg | 65 / 138 lb 29.5 / 62.6 kg | 101 / 193 lb 45.8 / 87.5 kg | 143 / 248 lb 64.9 / 112.5 kg | 187 / 303 lb 84.8 / 137.4 kg |
| 190 lb 86.2 kg | 67 / 143 lb 30.4 / 64.9 kg | 105 / 200 lb 47.6 / 90.7 kg | 148 / 257 lb 67.1 / 116.6 kg | 194 / 314 lb 88 / 142.4 kg |
| 200 lb 90.7 kg | 69 / 148 lb 31.3 / 67.1 kg | 109 / 207 lb 49.4 / 93.9 kg | 153 / 266 lb 69.4 / 120.7 kg | 201 / 325 lb 91.2 / 147.4 kg |
| 210 lb 95.3 kg | 72 / 153 lb 32.7 / 69.4 kg | 112 / 214 lb 50.8 / 97.1 kg | 158 / 275 lb 71.7 / 124.7 kg | 207 / 336 lb 93.9 / 152.4 kg |
| 220 lb 99.8 kg | 74 / 158 lb 33.6 / 71.7 kg | 116 / 221 lb 52.6 / 100.2 kg | 163 / 283 lb 73.9 / 128.4 kg | 214 / 346 lb 97.1 / 156.9 kg |
| 230 lb 104.3 kg | 76 / 162 lb 34.5 / 73.5 kg | 119 / 227 lb 54 / 103 kg | 168 / 292 lb 76.2 / 132.4 kg | 220 / 357 lb 99.8 / 161.9 kg |
| 240 lb 108.9 kg | 78 / 167 lb 35.4 / 75.7 kg | 123 / 234 lb 55.8 / 106.1 kg | 173 / 300 lb 78.5 / 136.1 kg | 227 / 367 lb 103 / 166.5 kg |
| 250 lb 113.4 kg | 80 / 172 lb 36.3 / 78 kg | 126 / 240 lb 57.2 / 108.9 kg | 178 / 309 lb 80.7 / 140.2 kg | 233 / 377 lb 105.7 / 171 kg |
| 260 lb 117.9 kg | 83 / 176 lb 37.6 / 79.8 kg | 129 / 247 lb 58.5 / 112 kg | 182 / 317 lb 82.6 / 143.8 kg | 239 / 387 lb 108.4 / 175.5 kg |
| 270 lb 122.5 kg | 85 / 181 lb 38.6 / 82.1 kg | 133 / 253 lb 60.3 / 114.8 kg | 187 / 325 lb 84.8 / 147.4 kg | 245 / 397 lb 111.1 / 180.1 kg |
| 280 lb 127 kg | 87 / 185 lb 39.5 / 83.9 kg | 136 / 259 lb 61.7 / 117.5 kg | 192 / 333 lb 87.1 / 151 kg | 251 / 407 lb 113.9 / 184.6 kg |
| 290 lb 131.5 kg | 89 / 190 lb 40.4 / 86.2 kg | 139 / 265 lb 63 / 120.2 kg | 196 / 341 lb 88.9 / 154.7 kg | 257 / 416 lb 116.6 / 188.7 kg |
| 300 lb 136.1 kg | 91 / 194 lb 41.3 / 88 kg | 142 / 271 lb 64.4 / 122.9 kg | 201 / 348 lb 91.2 / 157.9 kg | 263 / 426 lb 119.3 / 193.2 kg |
Women’s Leg Extension vs Barbell Hack Squat Standards
How to read the table: The first number is Leg Extension; the second is Barbell Hack Squat. 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 | 29 / 57 lb 13.2 / 25.9 kg | 46 / 86 lb 20.9 / 39 kg | 69 / 109 lb 31.3 / 49.4 kg | 89 / 132 lb 40.4 / 59.9 kg |
| 110 lb 49.9 kg | 31 / 61 lb 14.1 / 27.7 kg | 49 / 92 lb 22.2 / 41.7 kg | 73 / 116 lb 33.1 / 52.6 kg | 95 / 141 lb 43.1 / 64 kg |
| 120 lb 54.4 kg | 33 / 65 lb 15 / 29.5 kg | 52 / 97 lb 23.6 / 44 kg | 78 / 123 lb 35.4 / 55.8 kg | 101 / 149 lb 45.8 / 67.6 kg |
| 130 lb 59 kg | 35 / 68 lb 15.9 / 30.8 kg | 55 / 103 lb 24.9 / 46.7 kg | 82 / 130 lb 37.2 / 59 kg | 106 / 157 lb 48.1 / 71.2 kg |
| 140 lb 63.5 kg | 36 / 72 lb 16.3 / 32.7 kg | 57 / 108 lb 25.9 / 49 kg | 86 / 137 lb 39 / 62.1 kg | 112 / 165 lb 50.8 / 74.8 kg |
| 150 lb 68 kg | 38 / 75 lb 17.2 / 34 kg | 60 / 113 lb 27.2 / 51.3 kg | 90 / 143 lb 40.8 / 64.9 kg | 117 / 173 lb 53.1 / 78.5 kg |
| 160 lb 72.6 kg | 40 / 78 lb 18.1 / 35.4 kg | 63 / 118 lb 28.6 / 53.5 kg | 94 / 149 lb 42.6 / 67.6 kg | 122 / 181 lb 55.3 / 82.1 kg |
| 170 lb 77.1 kg | 41 / 82 lb 18.6 / 37.2 kg | 65 / 123 lb 29.5 / 55.8 kg | 98 / 155 lb 44.5 / 70.3 kg | 127 / 188 lb 57.6 / 85.3 kg |
| 180 lb 81.6 kg | 43 / 85 lb 19.5 / 38.6 kg | 68 / 128 lb 30.8 / 58.1 kg | 102 / 161 lb 46.3 / 73 kg | 132 / 195 lb 59.9 / 88.5 kg |
| 190 lb 86.2 kg | 44 / 88 lb 20 / 39.9 kg | 70 / 132 lb 31.8 / 59.9 kg | 105 / 167 lb 47.6 / 75.7 kg | 137 / 203 lb 62.1 / 92.1 kg |
| 200 lb 90.7 kg | 46 / 91 lb 20.9 / 41.3 kg | 73 / 137 lb 33.1 / 62.1 kg | 109 / 173 lb 49.4 / 78.5 kg | 142 / 210 lb 64.4 / 95.3 kg |
| 210 lb 95.3 kg | 48 / 94 lb 21.8 / 42.6 kg | 75 / 141 lb 34 / 64 kg | 113 / 179 lb 51.3 / 81.2 kg | 146 / 217 lb 66.2 / 98.4 kg |
| 220 lb 99.8 kg | 49 / 97 lb 22.2 / 44 kg | 77 / 146 lb 34.9 / 66.2 kg | 116 / 185 lb 52.6 / 83.9 kg | 151 / 223 lb 68.5 / 101.2 kg |
| 230 lb 104.3 kg | 51 / 100 lb 23.1 / 45.4 kg | 80 / 150 lb 36.3 / 68 kg | 120 / 190 lb 54.4 / 86.2 kg | 156 / 230 lb 70.8 / 104.3 kg |
| 240 lb 108.9 kg | 52 / 103 lb 23.6 / 46.7 kg | 82 / 155 lb 37.2 / 70.3 kg | 123 / 196 lb 55.8 / 88.9 kg | 160 / 237 lb 72.6 / 107.5 kg |
How Your Leg Extension vs Barbell Hack Squat 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 leg extension strength level
The leg extension standards use the sex-specific standards 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 extend more displayed resistance without requiring strength to increase pound for pound.
3. Find the barbell hack squat strength level
The barbell hack squat standards use the sex-specific standards from the individual Barbell Hack Squat 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 squat more total weight 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 leg extension | Adjust leg extension targets to exact bodyweight with the two-thirds rule. |
| Rate the barbell hack squat | Adjust barbell hack squat 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 Leg Extension and Barbell Hack Squat 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 barbell hack squat standard is higher; below zero means the leg extension 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.
39.9 → 73.9 kg from 120 to 300 lb bodyweight.
How to read the table: Every number is the barbell hack squat standard minus the leg extension standard. A plus sign means the barbell hack squat standard is higher. A minus sign means the leg extension standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 120 lb 54.4 kg | +56 lb +25.4 kg | +70 lb +31.8 kg | +80 lb +36.3 kg | +88 lb +39.9 kg |
| 130 lb 59 kg | +59 lb +26.7 kg | +73 lb +33.1 kg | +85 lb +38.5 kg | +93 lb +42.2 kg |
| 140 lb 63.5 kg | +62 lb +28.2 kg | +77 lb +34.9 kg | +89 lb +40.4 kg | +98 lb +44.4 kg |
| 150 lb 68 kg | +65 lb +29.4 kg | +81 lb +36.8 kg | +94 lb +42.6 kg | +102 lb +46.3 kg |
| 160 lb 72.6 kg | +68 lb +30.9 kg | +84 lb +38.1 kg | +97 lb +44 kg | +107 lb +48.5 kg |
| 170 lb 77.1 kg | +71 lb +32.2 kg | +89 lb +40.4 kg | +102 lb +46.3 kg | +112 lb +50.8 kg |
| 180 lb 81.6 kg | +73 lb +33.1 kg | +92 lb +41.7 kg | +105 lb +47.6 kg | +116 lb +52.6 kg |
| 190 lb 86.2 kg | +76 lb +34.5 kg | +95 lb +43.1 kg | +109 lb +49.5 kg | +120 lb +54.4 kg |
| 200 lb 90.7 kg | +79 lb +35.8 kg | +98 lb +44.5 kg | +113 lb +51.3 kg | +124 lb +56.2 kg |
| 210 lb 95.3 kg | +81 lb +36.7 kg | +102 lb +46.3 kg | +117 lb +53 kg | +129 lb +58.5 kg |
| 220 lb 99.8 kg | +84 lb +38.1 kg | +105 lb +47.6 kg | +120 lb +54.5 kg | +132 lb +59.8 kg |
| 230 lb 104.3 kg | +86 lb +39 kg | +108 lb +49 kg | +124 lb +56.2 kg | +137 lb +62.1 kg |
| 240 lb 108.9 kg | +89 lb +40.3 kg | +111 lb +50.3 kg | +127 lb +57.6 kg | +140 lb +63.5 kg |
| 250 lb 113.4 kg | +92 lb +41.7 kg | +114 lb +51.7 kg | +131 lb +59.5 kg | +144 lb +65.3 kg |
| 260 lb 117.9 kg | +93 lb +42.2 kg | +118 lb +53.5 kg | +135 lb +61.2 kg | +148 lb +67.1 kg |
| 270 lb 122.5 kg | +96 lb +43.5 kg | +120 lb +54.5 kg | +138 lb +62.6 kg | +152 lb +69 kg |
| 280 lb 127 kg | +98 lb +44.4 kg | +123 lb +55.8 kg | +141 lb +63.9 kg | +156 lb +70.7 kg |
| 290 lb 131.5 kg | +101 lb +45.8 kg | +126 lb +57.2 kg | +145 lb +65.8 kg | +159 lb +72.1 kg |
| 300 lb 136.1 kg | +103 lb +46.7 kg | +129 lb +58.5 kg | +147 lb +66.7 kg | +163 lb +73.9 kg |
How Women’s Leg Extension and Barbell Hack Squat Standards Differ
What the women’s data shows:
The standards come closest at 100 lb.
Novice, Intermediate, Advanced, and Elite at every displayed bodyweight.
19.5 → 34.9 kg from 100 to 240 lb bodyweight.
How to read the table: Every number is the barbell hack squat standard minus the leg extension standard. A plus sign means the barbell hack squat standard is higher. A minus sign means the leg extension standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 100 lb 45.4 kg | +28 lb +12.7 kg | +40 lb +18.1 kg | +40 lb +18.1 kg | +43 lb +19.5 kg |
| 110 lb 49.9 kg | +30 lb +13.6 kg | +43 lb +19.5 kg | +43 lb +19.5 kg | +46 lb +20.9 kg |
| 120 lb 54.4 kg | +32 lb +14.5 kg | +45 lb +20.4 kg | +45 lb +20.4 kg | +48 lb +21.8 kg |
| 130 lb 59 kg | +33 lb +14.9 kg | +48 lb +21.8 kg | +48 lb +21.8 kg | +51 lb +23.1 kg |
| 140 lb 63.5 kg | +36 lb +16.4 kg | +51 lb +23.1 kg | +51 lb +23.1 kg | +53 lb +24 kg |
| 150 lb 68 kg | +37 lb +16.8 kg | +53 lb +24.1 kg | +53 lb +24.1 kg | +56 lb +25.4 kg |
| 160 lb 72.6 kg | +38 lb +17.3 kg | +55 lb +24.9 kg | +55 lb +25 kg | +59 lb +26.8 kg |
| 170 lb 77.1 kg | +41 lb +18.6 kg | +58 lb +26.3 kg | +57 lb +25.8 kg | +61 lb +27.7 kg |
| 180 lb 81.6 kg | +42 lb +19.1 kg | +60 lb +27.3 kg | +59 lb +26.7 kg | +63 lb +28.6 kg |
| 190 lb 86.2 kg | +44 lb +19.9 kg | +62 lb +28.1 kg | +62 lb +28.1 kg | +66 lb +30 kg |
| 200 lb 90.7 kg | +45 lb +20.4 kg | +64 lb +29 kg | +64 lb +29.1 kg | +68 lb +30.9 kg |
| 210 lb 95.3 kg | +46 lb +20.8 kg | +66 lb +30 kg | +66 lb +29.9 kg | +71 lb +32.2 kg |
| 220 lb 99.8 kg | +48 lb +21.8 kg | +69 lb +31.3 kg | +69 lb +31.3 kg | +72 lb +32.7 kg |
| 230 lb 104.3 kg | +49 lb +22.3 kg | +70 lb +31.7 kg | +70 lb +31.8 kg | +74 lb +33.5 kg |
| 240 lb 108.9 kg | +51 lb +23.1 kg | +73 lb +33.1 kg | +73 lb +33.1 kg | +77 lb +34.9 kg |
Leg Extension and Barbell Hack Squat Exercises Used by This Calculator
This calculator uses a bilateral machine leg extension and a free-weight barbell hack squat. Do not substitute a single-leg, cable, band, or partial leg extension, or a machine, Smith-machine, partial, bounced, or hinge-dominant hack squat. The two entered weights use different equipment meanings.
Use a strict bilateral leg extension
Use both legs on the same dedicated machine and setup. Keep the hips, thighs, and torso stable, extend from a controlled flexed-knee start to a near-straight finish, and return under control. Do not enter per-leg load, a single-leg rep, partial pulse, bounced stack, cable or band extension, squat, or leg press.
Keep the bar behind the legs for a strict barbell hack squat
Keep the bar behind the legs throughout, descend under control to a consistent depth, and stand to full lockout with stable knees and torso. Do not enter a machine or Smith hack squat, partial rep, bounced rep, assisted setup, or hinge-dominant deadlift substitution.
Enter one recent leg extension set and one recent barbell hack squat set
Enter the displayed bilateral machine resistance for Leg Extension and total barbell weight for Barbell Hack Squat, plus a whole number from 1 to 12 reps for each. Pounds and kilograms can be mixed. Use clean, difficult sets that meet the definitions shown.
Related Tools
- Leg Extension — View the individual Leg Extension standards and next strength-level target.
- Barbell Hack Squat — View the individual Barbell Hack Squat standards and next strength-level target.
- Machine Hack Squat — 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.