Slopesense

Slopesense is a browser-based GPX analyzer for trail and ultra runners doing race recon. Drop a .gpx file and it finds the climbs and descents, draws a color-coded elevation profile, and rates each section's runability — so you know where you'll run, where you'll hike, and where the descents will wreck your quads.

Privacy: all parsing and analysis run entirely in your browser. No file is ever uploaded.

Develop

pnpm install
pnpm dev        # http://localhost:3000
pnpm test       # Vitest unit tests for the lib/ analysis engine
pnpm typecheck  # tsc --noEmit
pnpm build      # production build

Built with Next.js (App Router), TypeScript (strict), Tailwind CSS and Chart.js. The analysis core lives in lib/ as pure, framework-free, unit-tested functions.