Strength
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the Number.
Estimated 1RMs from submax sets. Plate math by bar and unit. Strength benchmarks with bias labelled, not glorified. Sourced to peer-reviewed sport science — or labelled house methodology when no consensus exists.
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Quick answers about StrengthMath's calculators and how the numbers work. Free, no signup. Not coaching or medical advice — for programming work with a qualified strength coach (NSCA CSCS, USAW, or equivalent), and for pain or injury work with a sports-medicine physician or physical therapist.
Hi, I'm the StrengthMath assistant. I answer questions about strength-training math — 1RM estimation, percentage-of-1RM programming, plate loading, dumbbell-vs-barbell comparison, strength-standards reading — and how the calculators on this site work. I'm not a strength coach or sports-medicine professional and can't program for your specific physiology, training history, or competition goals. For programming or pain/injury, work with a qualified strength coach (NSCA CSCS, USAW, equivalent) or a sports-medicine physician.
The lineup
5 calculators · all liveEpley · Brzycki · Lombardi · O'Conner. Per-formula spread + StrengthMath confidence bands (informed by LeSuer 1997) + suggested training max.
Lift-prefilled. Incline-to-flat ratio surfaced honestly.
Per-DB + total. Barbell-equivalent in a labelled range, not a verdict.
Strength · power · hypertrophy · peaking. NSCA + ACSM 2026 dual-framing.
Per-side loading order by bar, unit, and plate set.
26 articles. Sourced.
Bench / squat / deadlift / overhead-press standards by age & bodyweight. 1RM math from reps. Cross-lift ratios with engine vs. practitioner-consensus framed honestly. AAP youth guidance woven through every teen-mode article.