- Add unlimited watches with photos, brand, model, movement, and serial number.
- Tag and organize your timepieces for easy reference.
- Track historical accuracy and performance trends over time.
Measure Watch Accuracy with Atomic Precision
ChronoLog is the ultimate watch accuracy tester and timegrapher app for enthusiasts, watchmakers, and collectors. Using advanced atomic clock synchronization, ChronoLog lets you measure your mechanical watch or quartz timepiece with microsecond accuracy. Whether you're regulating a vintage chronometer or tracking your daily wearer, ChronoLog delivers professional-grade watch timing tools in an intuitive, ad-free experience.
Three Precision Measurement Modes
Quick-Tap Watch Accuracy Check
Record your watch time instantly against an atomic reference.
Photo-Measurement Watch Accuracy Check
Capture your dial, analyze the offset, and calculate daily rate variation.
Audio Timegrapher Measurement
Place your watch near your phone's microphone to measure rate and beat error using the tick sound — just like a professional timegrapher.
Full Watch Collection Management
Advanced Analysis & Tools
- Microsecond-accurate watch timing via atomic NTP sync.
- Graphs and charts showing drift, offset, and daily rate changes.
- Export your accuracy logs to CSV for deeper analysis.
- Audio-based measurement: use your watch's tick sound to measure rate and beat error — like a professional timegrapher, right from your phone.
Want to learn more about audio measurement? Check out our Timegrapher page for details on how ChronoLog turns your phone into a precision timing instrument.
Why Choose ChronoLog?
Unlike other timegrapher apps, ChronoLog combines precision measurement with powerful watch collection tracking — all in a clean, ad-free interface. It's built for serious collectors, professional watchmakers, and anyone who values true watch accuracy.
Stay on Time — Always
Download ChronoLog today and take control of your watch accuracy. Whether you're fine-tuning a movement or simply tracking performance, ChronoLog gives you the professional tools to keep every watch running at its best.