# Noise Calc > Calculator for estimating outdoor and semi-reverberant noise levels. (iPhone/iPad app by Lorenzo Rizzi.) - Source: https://appshunter.io/ios/app/noise-calc/id1556882174 (this page in markdown: same URL + `.md`) - Developer: [Lorenzo Rizzi](https://appshunter.io/developer/856070642) - Category: Utilities - Price: Free - Rating: 1.00/5 from 1 App Store ratings - Age rating: 4+ - Requires: iOS 15.1 · 39 MB - Languages: English - Released: 2021-07-31 - Data updated: 2026-06-05 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/noise-calc/id1556882174/reviews.md ## What is Noise Calc? Noise Calc is a calculator designed to quickly estimate noise levels in outdoor environments and semi-reverberant fields. It is a useful tool for acoustic technicians in the field, as well as for other professionals dealing with machine noise. We have specifically designed a section for those who design and install heat pumps, air handling units (AHUs), chillers, and other noisy outdoor machinery. The first section performs logarithmic summation in decibels: this is useful, for example, when multiple machines are nearby, and their known sound energy levels need to be summed (dB values must be added with dB, or dBA with dBA; sound power levels (Lw) can be summed together; sound pressure levels (Lp) can also be summed, but only if measured at the same distance from the source). The second section performs a logarithmic difference in decibels: this is useful when the ambient pressure level and residual pressure level are known, helping to determine the energy level of the sound source at a given point. The third section evaluates sound pressure attenuation with distance: if the pressure level (Lp) in decibels is known at distance d1, the result at d2 can be estimated (however, measurements taken with a phone should be avoided, and care must be taken to ensure that d1 is not too close to the source and that d2 is not affected by sound reflections). The fourth section evaluates sound propagation in free-field conditions, considering the sound power level (Lw) of the source and whether it is near one, two, or three surfaces (excluding reflections from other objects). The fifth section estimates the noise reduction effect of a sound-insulating barrier. It performs a simplified frequency-by-frequency calculation and returns the number of decibels by which the noise will be reduced (if the frequency is unknown, 500 Hz is typically used). The sixth section is particularly useful for technicians and installers of outdoor machinery. Given the data from the technical sheet (either power or pressure at the manufacturer-declared distance), the machine's position near one or more surfaces, and the distance to the nearest neighbor's window, the app will indicate whether there are significant issues in complying with municipal noise zoning regulations). The seventh section allows for a differential limit calculation. The eighth section evaluates sound propagation in a semi-reverberant field. ## Key features - Logarithmic summation of decibels - Logarithmic difference in decibels - Sound pressure attenuation with distance - Free-field sound propagation - Sound-insulating barrier noise reduction - Outdoor machinery noise compliance estimation ## Frequently asked questions about Noise Calc ### What is Noise Calc used for? Noise Calc is a calculator designed to estimate noise levels in outdoor environments and semi-reverberant fields. It's useful for acoustic technicians and professionals dealing with machine noise. ### Does Noise Calc have ads? No, Noise Calc does not contain advertisements. It is a completely ad-free application. ### What devices support Noise Calc? Noise Calc is available for iPhone and iPod devices. It is designed for iOS users. ### How often is Noise Calc updated? The latest version of Noise Calc is 2.6.0, last updated on April 22, 2026. This indicates a recent update, suggesting ongoing development and support. ### What is the age rating for Noise Calc? Noise Calc has an age rating of 4+. This means it is suitable for children aged 4 and above. ### Can Noise Calc calculate sound pressure attenuation? Yes, Noise Calc has a section that evaluates sound pressure attenuation with distance. It can estimate the sound pressure level at a different distance if the level at one distance is known. ### What is the user rating for Noise Calc? Noise Calc has a rating of 1.0 stars from 1 rating. This indicates very limited user feedback currently available. ### Is Noise Calc free to download? Yes, Noise Calc is available for free. There are no costs associated with downloading or using the application. ## Version history (last 5 releases) ### 2.6.0 — 2026-04-22 Updated to iOS 26 ### 2.5.2 — 2025-03-11 Fix bug missing links ### 2.4.0 — 2025-03-04 bug fix linear source propagation calculation transition frequency estimation to separate modal region from diffusive Sabinian region ### 2.3.1 — 2023-02-05 2 added tabs: - Sound level through a partition - Axial mode calculation in a standard rectangular-shaped room Minor fixes ### 2.2.0 — 2022-03-07 New tab: semi-riverberant field. New tab: differential level. New feature: move results from tabs to differential level tab. ## Apps similar to Noise Calc | App | Rating | Price | Category | | --- | --- | --- | --- | | [Building Acoustics Pro](https://appshunter.io/ios/app/building-acoustics-pro/id1670904136) | — | Free | Utilities | | [On-Axis](https://appshunter.io/ios/app/on-axis/id6446842774) | 5.0 (6) | Free | Utilities | | [Svantek Assistant Pro](https://appshunter.io/ios/app/svantek-assistant-pro/id1605934876) | — | Free | Utilities | | [Work Noise Partner](https://appshunter.io/ios/app/work-noise-partner/id1455628087) | 5.0 (1) | Free | Utilities | | [OpeNoise](https://appshunter.io/ios/app/openoise/id1387499991) | 4.0 (4) | Free | Utilities | | [Product Noise Partner](https://appshunter.io/ios/app/product-noise-partner/id1503175697) | — | Free | Utilities | ## More apps by Lorenzo Rizzi - [APM Tool Lite](https://appshunter.io/ios/app/apm-tool-lite/id891304617) - [APM Sweep](https://appshunter.io/ios/app/apm-sweep/id1492480271) All apps by Lorenzo Rizzi: https://appshunter.io/developer/856070642 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-05.*