Estimate a one-rep max (1RM) from a weight lifted for a number of reps, using Brzycki, Epley, Lander, Lombardi, Mayhew, O'Conner, and Wathen formulas. Returns the chosen formula result, every formula result, and a training-weight table (100% to 60%) with rep ranges and zones.
This page documents the HTTP endpoint POST /api/tools/one-rep-max-calculator/execute. See the MCP reference →
Call it over REST
POST https://api.findutils.com/api/tools/one-rep-max-calculator/execute · no API keys · 60 requests/min per IP
Execute — verified arguments
curl -X POST https://api.findutils.com/api/tools/one-rep-max-calculator/execute \
-H "Content-Type: application/json" \
-d '{
"weight": 100,
"reps": 5
}'Parameter schema for this endpoint
curl https://api.findutils.com/api/tools/one-rep-max-calculatorInput schema
| Argument | Type | Required | Description |
|---|---|---|---|
| weight | number | yes | Weight lifted, in the chosen unit. |
| reps | integer | yes | Reps performed with that weight (1-30). |
| unit | string (kg | lbs) | no | Weight unit, echoed back in the result. Default: "kg". |
| formula | string (brzycki | epley | lander | lombardi | mayhew | oconner | wathen) | no | Formula used for the headline one_rep_max. Default: "brzycki". |
Example arguments (verified)
{
"weight": 100,
"reps": 5
}Also an MCP tool
Claude, Cursor, and any MCP client can call this tool as
findutils:one_rep_max_calculator after one connect command.
Connect once
claude mcp add findutils --transport http https://mcp.findutils.com/More Calculators tools
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