How accurate are these 1RM estimates?

Estimates are most accurate when repetitions are 12 or fewer. For higher rep counts, the `validate_lift_integrity` tool can flag if the estimation may be unreliable.

Can I use this for both kilograms and pounds?

Yes, all tools support both 'kg' and 'lbs' units.

RPE stands for Rate of Perceived Exertion. You can use `get_rpe_equivalence` to estimate how much effort a specific weight and repetition count requires on a standard scale.

One-Rep Max Calculator MCP Connector for Claude

A+

Estimate 1RM strength, training intensity zones, and RPE from submaximal lifts.

3 tools Official Updated Oct 1, 2026 Official Vinkius Partner

More Details Connect to Claude

This MCP server provides a deterministic toolset for strength athletes and coaches to estimate one-repetition maximum (1RM) using established physiological models. By inputting weight and repetitions, you can access multiple estimation formulas including Epley, Brzycki, and Lombardi. The server also calculates training intensity zones for various rep ranges and maps lifts to their estimated Rate of Perceived Exertion (RPE). Use calculate_1rm_metrics for a full strength profile or get_rpe_equivalence to determine how hard a set felt.

weightlifting1rmstrengthfitnesstraining

Connect to Claude

Subscribe on Vinkius, then add this connector to Claude.ai or Claude Code.

① Claude.ai (web app)

Go to Settings → Connectors → Add custom connector
Paste the MCP endpoint URL below

https://edge.vinkius.com/vk_preview_aPKoxSry2XjrT9Eam1RwAIJ89uGLNjyfXKC9BS1r/mcp

② Claude Code (terminal)

claude mcp add --transport http one-rep-max-calculator-1 https://edge.vinkius.com/vk_preview_aPKoxSry2XjrT9Eam1RwAIJ89uGLNjyfXKC9BS1r/mcp

③ Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "one-rep-max-calculator-1": {
      "url": "https://edge.vinkius.com/vk_preview_aPKoxSry2XjrT9Eam1RwAIJ89uGLNjyfXKC9BS1r/mcp"
    }
  }
}

Get full access on Vinkius

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