About This Calculator

A small tool for everyone who runs

Hello! I'm the developer behind the All-in-One Running Calculator—a fellow runner obsessed with Zone 2 training, tempo sessions, and sustainable mileage. The goal was simple: gather marathon pace prediction, treadmill pace conversion, MAF heart-rate planning, and fueling math on a single responsive page.

🤔 Why Did I Build This?

During training blocks I kept juggling multiple tabs to answer questions like “What marathon time does my 10K translate to?”, “How fast should 400m reps be for VO₂max intervals?”, or “Where does my Maffetone cap fall today?”. Scattered data and clunky mobile UI/UX slowed everything down, so I built a unified tool.

"One intuitive dashboard for race prediction, treadmill pace conversion, Zone 2 / MAF guidance, and fueling estimates—no spreadsheets required."

🧰 What's Inside?

  • Race Predictor & Split Planner — Riegel-based goal times, weather offsets, CSV pace plans, and 1 km/5 km split tables.
  • Zone 2 · MAF · LT Tools — % Max HR vs. Karvonen, Maffetone 180, plus an LT calculator that suggests tempo and cruise-interval intensities automatically.
  • Treadmill & Track utilities — Instant km/h ↔ min/km and mph ↔ min/mile conversion, with 400 m lap splits for track sessions.
  • Marathon Schedule Page — Automatically updated major race dates and registration links for Korea and global events.

🎯 What We Value

Every feature is grounded in evidence—Riegel, Karvonen, Maffetone, 80/20 endurance theory, and current LT research—so you can train longer without injury. All calculations run locally in the browser, meaning no personal data ever leaves your device and Garmin/Strava exports pair seamlessly with the results.

📚 Stay Up to Date

The latest race timeline is maintained on the Marathon Schedule page, while product roadmap updates are posted here on About. The Korean edition mirrors each change.