NoiseLedger: Decibel Meter
dB, SPL, noise & sound log
About
Measure sound levels with real-time decibel readings and detailed noise logging. Analyze audio with frequency weighting, spectrograms, and create professional reports. This privacy-focused tool keeps all data on your device.
What's New in NoiseLedger
2.0
August 25, 2026
NoiseLedger 2.0 is our biggest update yet — and everything is still free, with no ads. NEW: Noise dosimeter with NIOSH and OSHA standards, live dose %, TWA and time-to-limit projection. NEW: Percentiles L10/L50/L90/L95, time above threshold and dB histogram. NEW: Spectrogram waterfall and 31 third-octave bands with peak hold. NEW: Multi-page PDF report with a threshold-exceedance table — ideal for documenting a noise problem. NEW: Overnight recording with adaptive sampling, auto-stop timer and a quiet night preset. NEW: Trends dashboard with daily Leq, streaks and your loudest day and hour. NEW: Calibration wizard and offset profiles for ~30 iPhone models. NEW: iOS measurement mode disables audio processing so readings are not altered. NEW: History search, date and dB range filters, multi-select export and bulk delete. NEW: Share your settings as a QR preset. NEW: 43 languages. Thank you for measuring with NoiseLedger.
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FAQ
Does NoiseLedger have ads?
No, NoiseLedger is completely free and does not contain any advertisements. The app is designed with a privacy-first approach and avoids trackers or analytics.
What devices does NoiseLedger support?
NoiseLedger is available for iPhone and iPod. It utilizes the built-in microphone, and the app includes calibration profiles for approximately 30 iPhone models.
How accurate are NoiseLedger's readings?
NoiseLedger uses the iPhone's built-in microphone, so readings are approximate and can vary by device. It is intended as a helpful indicator, not a certified instrument for legal or safety-critical measurements.
Can I record sound for extended periods with NoiseLedger?
Yes, NoiseLedger supports overnight and long-session recordings. It features adaptive sampling, an auto-stop timer, and a quiet night preset for continuous monitoring.
What kind of reports can I generate with NoiseLedger?
You can export professional multi-page PDF reports that include charts, statistics, percentiles, dose information, and a threshold-exceedance table. CSV and PNG formats are also available.
Is my data stored on the cloud with NoiseLedger?
No, NoiseLedger is privacy-first and does not use any cloud storage. All audio analysis and data logging are performed live and remain on your iPhone. You can erase all data at any time from the app's settings.
How often is NoiseLedger updated?
The latest version of NoiseLedger is 2.0, and it was last updated on August 25, 2026. This indicates a commitment to ongoing development and improvements.
What are the noise dosimeter standards supported by NoiseLedger?
NoiseLedger functions as a noise dosimeter according to NIOSH (85 dB, 3 dB) and OSHA (90 dB, 5 dB) standards. It provides live dose percentage, TWA, and time-to-limit projections.
