# clementwzk/OpenCalc

A simple and beautiful calculator for Android downloaded more than 300k times

Repository: https://github.com/clementwzk/OpenCalc
Canonical: https://ross.abutalabs.com/products/opencalc
Language: Kotlin
License: GPL-3.0
License Family: copyleft
Topics: android, apk, calculator, fdroid, fdroid-repos, kotlin, android-app, android-application, android-calculator
Last push: 2026-07-10T14:17:39+00:00

## Health v2 (maintenance only)
Score: 78/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 91, release rhythm 48, longevity 100
- inputs: {"age_days": 1507, "days_push": 54, "days_rel": 346, "gap_med": 1.5, "n_releases_24m": 7}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1518, forks 184 (observed 2026-08-28T04:04:57.416877+00:00)

## What it is
OpenCalc is a simple, lightweight, open-source calculator app for Android built in Kotlin. It offers scientific mode, calculation history, multiple themes including Material You, and is available via Google Play, F-Droid, and GitHub.

## Use cases
- replace the stock calculator on my Android phone
- open-source calculator app with no ads and no unnecessary permissions
- scientific calculator with history for Android
- small APK calculator that works offline
- calculator with dark and amoled themes
- calculator available on the lock screen
- fdroid calculator app with material you support

## When to choose
- you want a free, ad-free, privacy-respecting calculator on Android
- you need a lightweight calculator (~2MB APK) with scientific functions and history
- you prefer installing apps from F-Droid or GitHub instead of proprietary alternatives

## When to avoid
- you need graphing or advanced symbolic math capabilities
- you are not on Android (requires Android 5.0+)
- you need a calculator with unit conversion or currency features not listed

## Facets
- artifact type: application
- maturity: active
- function: gui
- domain: android-tools, developer-tools, cross-platform
- platform: -
- tags: calculator, scientific-calculator, open-source-android, fdroid, material-you, lightweight, android

## Member repositories
- clementwzk/OpenCalc (main) score 78

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:57.416877+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:32:00.859267+00:00, confidence not recorded.
  - readme: https://github.com/clementwzk/OpenCalc (fetched 2026-08-28T04:04:57.416877+00:00, sha 00bbbe251139)
- Data as of 2026-08-30T08:39:29.467469+00:00.