FOSS · Free

c2k

A free Couch-to-5K/10K running trainer, fully offline, no Google services required

c2k is a free, open-source running trainer for Android that guides you from the couch to running 5K, 10K, and beyond — with no ads and no tracking.

Programs

Pre-C25K — 3-week gentle starter for absolute beginners
Couch to 5K (C25K) — 9-week program, 3 runs per week
Bridge to 10K (B210K) — 6-week bridge for C25K graduates
Couch to 10K (C210K) — 14-week program, continues from C25K
One Hour Runner — 13-week progression from 30 to 60 minutes continuous running
5K Improver — 8-week speed and stamina program for runners who can already complete 5K

Audible voice prompts — "Start running", "Walk for 90 seconds", countdown warnings
Customizable coaching — adjust voice speed/volume, countdown warning timing, and mid-interval cues
Vibration cues as an alternative or addition to voice
Background workout timer — continues with the screen off
Optional GPS tracking — records distance and pace; works without GPS too
Treadmill mode — indoor runs without GPS
Workout history — session log with total distance, time, best pace, longest run, and calorie estimates
Progress tracking — remembers which weeks and days you've completed
Available in 7 languages — English, German, Spanish, French, Galician, Portuguese (Brazil), Russian
Works offline — no internet permission required
No proprietary services required — compatible with GrapheneOS and privacy-focused devices

c2k is free software released under the GNU General Public License v3.