MCP server
Add https://www.ironledger.app/mcp as a remote MCP server (Streamable HTTP, no sign-in) in Claude, ChatGPT or any MCP client. Server card: /.well-known/mcp/server-card.json.
// FREE TOOLS //
Strength calculators.
Free calculators for the numbers lifters work out between sets: an estimated max, a load for a target RPE, the plates for each side, a warm-up ramp and a powerlifting score. Plus a checker that shows how a program file will import into the IronLedger app. Every page shows its formula or rules and its sources, and needs no account.
One rep max calculator
Your estimated 1RM from any set, with a percentage table and the load each rep count should allow.
Same maths as the IronLedger appBench press calculator
Estimate your max bench from a set of reps, with bench-specific notes on what counts as a rep.
Same maths as the IronLedger appRPE calculator and chart
Turn RPE and reps into a percentage of your max, estimate a max from an RPE set, or find the load for a target.
Web toolPlate calculator
Which plates go on each side of the bar, for any bar, in kg or lb, with the plates you actually own.
Same maths as the IronLedger appWarm-up calculator
A plate-friendly warm-up ramp to your working weight, with the plates for every set.
Same maths as the IronLedger appDOTS calculator
Score a powerlifting total with DOTS, IPF GL points and Wilks, using the OpenPowerlifting coefficients.
Web toolProgram file checker
Check a CSV training program before you import it into IronLedger, with the file format spelled out for people and AI assistants.
Same rules as the app’s importer// HOW THEY’RE BUILT //
One function, every surface.
Each calculator is a single tested function. This site, the API and the MCP server all call it, so they can’t disagree.
- The one rep max, plate and warm-up maths are ported from the IronLedger app and checked against its own code.
- The program file checker runs the app’s own import rules, matched against the app’s importer on 35,000 generated files.
- Every formula is written out on its page, with a worked example and the source it comes from.
- Every result has its own link: change an input and the address updates, so you can share the exact result.
- Tables are real HTML tables, and every page is available as Markdown to assistants that ask for it.
// FOR AI ASSISTANTS AND DEVELOPERS //
Free API and MCP server.
The same calculators, read-only, with no account or key. Each answer comes with a one-line summary, the method used and a link to the result on this site.
JSON API
GET or POST /api/tools/<tool>, for example /api/tools/one-rep-max?weight=140&reps=5&unit=kg. Described in /openapi.json and listed at /.well-known/api-catalog.
Agent skill
A short SKILL.md explaining when and how to call the calculators: /.well-known/agent-skills/ironledger-strength-calculators/SKILL.md. Browser agents that support WebMCP also find the tools registered on every page.
| MCP tool | API path | What it does |
|---|---|---|
| one_rep_max | /api/tools/one-rep-max | One-rep max calculator |
| rpe_estimate_max | /api/tools/rpe-estimate-max | Estimate one-rep max from a set and its RPE |
| rpe_target_load | /api/tools/rpe-target-load | Load for a target reps and RPE |
| plate_loading | /api/tools/plates | Barbell plate calculator |
| warmup_sets | /api/tools/warm-up | Warm-up set calculator |
| powerlifting_score | /api/tools/powerlifting-score | DOTS, IPF GL and Wilks calculator |
| check_program_file | /api/tools/program-file | IronLedger program file checker |
Requests are rate limited per address. Results are estimates for planning training, not medical advice. Setup steps for each AI app