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About this tool
Calculate your estimated one-rep max weight using scientific formulas. Track your fitness progress with multiple calculation methods.
One Rep Max Calculator is a free fitness tool that runs entirely in your browser — nothing to install, no account to create, and your data never leaves your device. Open the page, add your input, and get a clean, copy-ready result in seconds.
Open One Rep Max Calculator on AltFTool — it loads instantly in your browser.
Enter the values you already know.
Fine-tune the options to match your scenario.
Read the result and use it in your planning or reporting.
Enter what you know and see an accurate result immediately — no formulas or spreadsheets required.
Adjust the inputs to see exactly how each change affects the outcome before you decide.
Take a clear, precise number into your plans, reports, or conversations.
Yes — One Rep Max Calculator is completely free on AltFTool, with no signup, no trial limits, and no hidden costs.
Yes. One Rep Max Calculator runs in your browser, so what you enter or upload stays on your device instead of being sent to a server.
Calculate your estimated one-rep max weight using scientific formulas. Track your fitness progress with multiple calculation methods. It's built for quick, everyday fitness tasks with results you can copy or download straight away.
Yes — One Rep Max Calculator works in any modern browser, on desktop, tablet, and mobile, with the same features everywhere.