health tools
One-Rep Max Calculator
Estimate a one-repetition maximum from a submaximal weight and completed repetitions.
Private by design
Enter your values
The estimate updates instantly and stays in this browser.
One idea, three depths
Choose how deeply to explain One-rep max
One-rep max: Estimate a one-repetition maximum from a submaximal weight and completed repetitions.
Age 5 Explain it to a 5-year-old Start with a picture
Imagine using a measuring rule to make a rough estimate about a body, workout or calendar while remembering that people do not all behave like averages. Estimate a one-repetition maximum from a submaximal weight and completed repetitions.
Age 15 Explain it to a 15-year-old Connect it to the formula
Estimate a one-repetition maximum from a submaximal weight and completed repetitions. The Epley and Brzycki equations extrapolate from the entered set. Technique, fatigue, exercise selection and high repetition counts affect the estimate. Change one input or choice at a time and compare the result to see which part of the rule it controls.
College Explain it at college level State the model precisely
The browser applies a published screening, energy, exercise or calendar-estimation formula to the supplied values. The result is educational and cannot diagnose, prescribe or replace individualized clinical guidance. The Epley and Brzycki equations extrapolate from the entered set. Technique, fatigue, exercise selection and high repetition counts affect the estimate. Entries remain in this browser. The output is an educational estimate, not medical advice, diagnosis or a treatment recommendation. Discuss health, pregnancy, nutrition and exercise decisions with an appropriately qualified professional.
How this tool works
The Epley and Brzycki equations extrapolate from the entered set. Technique, fatigue, exercise selection and high repetition counts affect the estimate.
Privacy and limitations
Your entries and results stay in this browser. This calculator provides an educational estimate only and cannot diagnose a condition, prescribe intake or exercise, establish pregnancy dates, or replace advice from a qualified health professional.
Authoritative context
Review the CDC adult BMI guidance, American Heart Association target-heart-rate guidance, and ACOG pregnancy-dating guidance when those subjects apply.
Reuse the page responsibly Cite this page APA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). One-Rep Max Calculator. MW SysArc Tools. https://health.mwsysarc.com/one-rep-max-calculator
MLA 9
MW SysArc. “One-Rep Max Calculator.” MW SysArc Tools, 21 July 2026, https://health.mwsysarc.com/one-rep-max-calculator. Accessed 13 Aug. 2026.
Chicago 17
MW SysArc. “One-Rep Max Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 13, 2026. https://health.mwsysarc.com/one-rep-max-calculator.
Harvard
MW SysArc (2026) ‘One-Rep Max Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://health.mwsysarc.com/one-rep-max-calculator (Accessed: 13 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_one_rep_max_calculator_2026,
author = {{MW SysArc}},
title = {One-Rep Max Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://health.mwsysarc.com/one-rep-max-calculator},
note = {Published July 21, 2026; accessed August 13, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - One-Rep Max Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-13
UR - https://health.mwsysarc.com/one-rep-max-calculator
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the One-rep max do?
Estimate a one-repetition maximum from a submaximal weight and completed repetitions.
How does the One-rep max work?
The Epley and Brzycki equations extrapolate from the entered set. Technique, fatigue, exercise selection and high repetition counts affect the estimate.
What can I learn from the One-rep max?
It shows how the entered values or choices produce the result. Change one input at a time to compare outcomes and understand the underlying rule.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
This is an educational estimate, not medical advice, diagnosis or a treatment recommendation. Health, nutrition, pregnancy and exercise decisions should be discussed with an appropriately qualified professional.
Last reviewed . Calculations tested .