Just what I was looking for
Works well on my iPhone
Free
About
This app analyzes the frequency of a plucked timing belt to help you tune it accurately. It provides real-time feedback, historical data, and includes calculators for tension and belt length.
✓Real-time frequency analysis
✓Live tuning indicator
✓Measurement history
✓Tension calculator
✓Belt length calculator
✓On-device processing
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What's New in Belty
1.1
August 2, 2026
Themes, improved settings, bug fixes
User reviews
FAQ
What is Belty used for?
Belty is used to measure the frequency of a plucked timing belt, providing real-time feedback to help you tune its tension accurately. It also includes calculators for tension and belt length.
Does Belty collect any user data?
No, Belty runs entirely on your device. It does not require an account, collect any data, or record audio. The microphone is solely used to listen to the belt.
What types of belts can Belty calculate tension for?
Belty supports a wide range of belts including GT2 (2mm/3mm), GT3 (3mm), HTD 3M, HTD 5M, MXL, XL, and custom belts from datasheets. It provides targets in Hz and newtons for loose, medium, and tight settings.
How does Belty provide tuning feedback?
Belty displays a live indicator that shows whether the belt is too tight, too loose, or on target. This allows for continuous adjustment without needing to stop and re-measure.
Can I save my measurements with Belty?
Yes, Belty allows you to save, name, and favorite any measurement or calculation you make. This history feature helps you keep track of your tuning sessions.
What devices is Belty available on?
Belty is currently available for iPhone devices. The app requires iOS 13.0 or later.
How often is Belty updated?
The latest version of Belty is 1.1, last updated on August 2, 2026. Updates typically focus on improving accuracy and adding support for more belt types.
Does Belty have ads?
No, Belty is completely ad-free. It is a free application with no advertisements to interrupt your workflow.