Workout Tracker

A functional slice of a training log built on Cloudflare Workers, seeded here with example data generated in this page — eight weeks of an invented linear-progression block. Log your own sets below and every chart, trend, and PR recomputes. Anything you enter stays in your own browser (localStorage); nothing leaves this page.

lb × reps

Estimated one-rep max, by session

Weekly tonnage

Personal records detected

What is running

Every set is a row: date, lift, weight, reps. From that single table the page derives estimated one-rep max per set with the Epley formula (w × (1 + r/30)), per-session bests per lift, weekly tonnage (Σ weight × reps), and PR detection — a chronological scan that flags any set whose e1RM beats everything before it for that lift. The deload dip in week six and the rep-PR spike in week eight are in the sample data on purpose: a trend line that can't survive a deload without panicking is a bad trend line. The production version keeps the same derivations server-side in D1 so history survives devices.

Why this matters, in plain terms: people quit training plans because progress is invisible week to week. The fix is the same as in any engineering system: measure honestly, derive the trend, and celebrate real milestones automatically. One simple table of sets becomes a strength trendline, a workload gauge that warns when you are overreaching, and an automatic record book — and the same measure-derive-alert pattern applies to sales pipelines and server fleets just as well as barbells.