Estimate one-rep max strength from weight lifted and reps with Epley and Brzycki formulas and training zones. No account needed and nothing is uploaded.
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Quick answer: One-Rep Max Calculator — Epley + Brzycki Free, no signup, runs in your browser. See below for the interactive tool, 4-step guide and FAQs.
90% of 1RM (avg)
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85% of 1RM (avg)
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80% of 1RM (avg)
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75% of 1RM (avg)
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Epley as weight times one and reps over thirty and Brzycki as weight times thirty-six over thirty-seven minus reps appear together. One hundred kilograms for five reps gives Epley 117 and Brzycki 113, so plan 112 to 117 range. Bar math runs here net-off, no keep. See /terms for scope.
General fitness information only, never clearance for maximal loading with injury risk. Injury, hypertension, pregnancy, and joint issues change safe loads substantially. Max attempts after pain need clinician clearance, not just percentages. Warm up, use spotters, and see /terms for details.
Estimates are best from one to ten reps, with three to five ideal for accuracy and safety. One hundred kilograms for five reps predicts 112 to 117 well, while sets above twelve overstate max and raise fatigue injury risk. Use sixty-five to eighty-five percent zones and see /terms.
Volume blocks use sixty-five to seventy-five percent for five-by-five, hypertrophy uses seventy to eighty, strength peaks at eighty-five to ninety-two. One hundred fifteen max gives seventy-five to eighty-six volume and ninety-eight to one hundred six peak. Cycling three-week waves with deload sustains progress while managing fatigue effectively.
Retest after six to eight weeks of structured progression, technique consolidation, or body-weight change over three kilograms. One hundred for five projecting 115 may understate after peaking cycle, so single at 100 then 110 then 115 validates. Prioritizing recovery, nutrition, and spotter safety prevents failed attempts decisively.
Epley multiplies weight by one and reps over thirty, Brzycki by thirty-six over thirty-seven minus reps, to project maximal single with different assumptions. One hundred kilograms for five reps gives Epley 117 and Brzycki 113, so plan near 112 to 117 range. Sixty-kilogram bench for eight reps projects about seventy-four offline private. Projection table compares lifts comprehensively | Load and reps performed | Epley estimate | Brzycki estimate | 100 for 5 reps | 117 max | 113 max | 60 for 8 reps | 76 max | 74 max | 80 for 3 reps | 88 max | 85 max. Edge case beyond ten reps overstates due to endurance bias significantly. Limitation assumes fresh submaximal set to near failure. Both formulas guide loading, not guarantee performance. This is general information only, not medical advice. See /terms.
Enter twenty to three hundred kilograms and one to twelve reps; tool shows both maxes and sixty-five to ninety-five percent zones for programming. Use sixty-five to seventy-five for volume, eighty to ninety for strength, with five-kilogram jumps. Above ten reps overstates by five percent due to fatigue modeling limits. Second example at eighty for three gives eighty-eight Epley and eighty-five Brzycki with seventy-five at sixty-five percent. Zone table maps intent clearly | Percent of max | Load for 115 max | Training use case | 65 percent | 75 kilograms | volume 5x5 base | 80 percent | 92 kilograms | strength triples | 90 percent | 104 kilograms | peaking singles. Edge case of grinding reps inflates estimate artificially. Limitation ignores bar speed, injury, peaking fatigue. Treat max as estimate, not guarantee, offline private. This is general information only, not medical advice. See /terms.
Lift one hundred for five with max 112 to 117, train seventy-five to one hundred across zones, retest in six weeks offline with no upload needed. Cap attempts at one to three reps with spotters and full warm-up including empty bar and ramp sets. Test sixty bench for eight projecting seventy-four to scale across lifts with different rep ranges. Verify eighty for three projecting eighty-five to eighty-eight for strength focus. Edge case of failed final rep suggests using four-rep value for safety and conservatism. Limitation excludes technique breakdown under true maximal load and psychological arousal. This is general information only, so see /terms and get coaching for heavy singles. For fuel needs try guide at /calorie-calculator free offline with private computation and macro planning.