ClapReverb2.3.3 - App Store

Measure the acoustics of a room... with a simple clap
ClapReverb lets you instantly evaluate the reverberation time (RT) of an enclosed space - a key factor in determining a room’s acoustic quality. Is the room too echoey? Or too dry? Get the answer in just a few seconds.

Simple, fast, and precise
With a clean design and intuitive interface, all it takes is a quiet moment and five hand claps. Place your phone or tablet at the center of the room, wait for the signal, and clap your hands (slightly cupped palms). The app analyzes the relevant frequencies and provides a clear picture of the room's acoustics.

A professional tool, accessible to everyone
Whether you’re an architect, interior designer, engineer, teacher, musician - or simply curious - ClapReverb is for anyone who wants to integrate acoustics into their projects. Easily compare your results to typical reference values and decide if acoustic treatment is needed.

Scientifically validated
The app’s results have been verified through a rigorous experimental protocol, presented at the 26th International Congress on Sound & Vibration.

Your feedback helps us improve.
Questions or suggestions? Write to us at clapreverb@atelier7hz.com. We’d love to hear from you!

Version History Compliance with the new Apple requirements. 2.3.3 Jan 25 Fix for app crash when a Bluetooth device is connected 2.3.2 06/30/2025 Minor changes and debug (tutorial and reviews) 2.3.1 03/31/2025 - New user interface: sleek, smooth, dynamic, and responsive on all screen sizes
- Changed sound notification between claps
- Added usage tips for better accuracy
- Minor bug fixes 2.3.0 03/24/2025 Removal of audio feedback (successful test on iPhone 7, iPhone Xs and iPhone 12) 2.2.3 03/06/2023 - iOS 16 bug solved

- Note: app is not optimized for iPad
- If the app crashes, uninstall and reinstall the app (data will be lost) 2.2.2 12/12/2022 - Minor changes for iOS13 support
- Results validated by a rigorous and robust experimental protocol (publication of the results at the 26th International Congress on Sound & Vibration)
- Note: app is not optimized for iPad
- If the app crashes, uninstall and reinstall the app (data will be lost) 2.2.1 05/21/2020 - iOS 13 support
- Calculation method improvement: good accuracy and reliability of the results for reverberation time under 0.25s
- User interface updates: new sound wave graphic, minor changes
- Results validated by a rigorous and robust experimental protocol (publication of the results at the 26th International Congress on Sound & Vibration)
- Note: app is not optimized for iPad
- If the app crashes, uninstall and reinstall the app (data will be lost) 2.2 02/18/2020 - Adding a module giving simplified recommandations on room acoustics
- Graphic update: new logo and updated design of screens
- Fixed a bug in data storage and deletion
- Small changes in the calculation method and messages
- Note: app is not optimized for iPad
- If the app crashes, uninstall and reinstall the app (data will be lost) 2.1 08/27/2019 - Improved calculation method: the algorithms ensure a better accuracy and reliability of the results
- Validation of results by a rigorous and robust experimental protocol (publication of the results at the 26th International Congress on Sound & Vibration)
- Graphical interface optimized for more clarity
- The final update of the interface and recommendation module is coming soon!
- If the application crashes, uninstall and reinstall the app 2.0 07/11/2019 1.0 11/07/2018