Can I code this? A Personal Fitness/Workout Tracker
Logging exercises, sets, and reps against a workout history is straightforward CRUD. If you want it fed by wearable hardware instead of manual entry, that's Whoop's problem, not this one's.
Borderline
Effort: a weekendRunning cost: $0/mo to start
Why CanICodeThis says Borderline
Exercises, sets, reps, and weight logged per workout session is ordinary CRUD
Personal records and progress charts over time are standard aggregation and charting
A library of exercises with instructions is straightforward content
The parts that'll cause problems
Pulling data automatically from a wearable device needs that device's specific API, and quality varies a lot by manufacturer
Workout plan generation (auto-suggesting your next session based on progress) is a real, separate feature beyond logging
Social features (sharing workouts, following friends) add real network-effect complexity this idea doesn't need to start
How I'd build this
frontend
Next.js
database
Supabase
auth
Supabase Auth
hosting
Vercel / Cloudflare Pages
MVP scope
Log exercises, sets, reps, and weight per session
Personal record tracking per exercise
Progress charts over time
A basic exercise library
Postpone to v2
Wearable device data import
Auto-generated workout plans
Social sharing and following
What it actually costs to build
AI agent — with a subscription (Claude Pro/Max, Cursor, etc.)
$0 marginal
AI agent — pay-per-use API, no subscription
$43–$86 one-time
Hosting, once it's running
$0/mo (free tier)
Domain name, if you want your own
~$12/yr
Existing tools solving a similar problem typically run $11.99–$30/mo — see how they compare below.
The build prompt
Build me a workout tracker: log exercises, sets, reps, and weight per session, track personal records per exercise, and show progress charts over time. A basic library of common exercises with instructions. SQLite or Supabase behind a small API, single-user login. Skip wearable integration and social features for v1.