OneCalc Pro
One Calculator, Calm & Smart
Free · In‑App Purchases
One calm, capable calculator that replaces a dozen apps cluttering your Home Screen.
OneCalc brings together everyday maths, scientific functions, currency and unit conversion, and a genuinely useful pay tracker — all in one beautifully simple app, with no ads, no accounts, and no data leaving your device.
Standard and scientific calculator
Switch instantly between a clean everyday calculator and full scientific functions, with a scrollable history so you never lose a previous sum.
Pay and overtime tracker
Built for shift workers. Add jobs and pay rates, set night and weekend multipliers, and watch your earnings update live as you work. No spreadsheets, no guesswork.
Scan and Solve
Point your camera at a maths problem — textbook, worksheet, whiteboard — and get a clear, step-by-step AI-powered solution in seconds.
Live currency, unit and time conversion
Convert between 30+ currencies using official ECB rates, with full offline support. Unit, time and percentage converters are built right in for travel, cooking, work or study.
Discounts and loans, sorted
Work out sale prices and savings instantly, or calculate loan repayments before you commit. Practical tools, no faff.
Make it yours
Choose from 9 accent themes to match your style, use the Apple Watch app for calculations on the go, and add the interactive widget to your Home Screen for instant access.
OneCalc is free to download and use for standard and scientific calculations. Premium unlocks the pay tracker, Scan & Solve, currency conversion, loan and discount calculators, and all themes, with a 3-day free trial. Premium is available as a £9.99 per year subscription or a £29.99 one-time lifetime purchase — your choice, no pressure.
One app instead of many. No ads. No accounts. Your data stays on your device.
Download OneCalc and see how calm a calculator can feel.
https://annmarstudio.co.uk/onecalc/terms
https://annmarstudio.co.uk/onecalc/privacy
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Calculations now always follow the order of operations, plus fixes for negative numbers and percentages. Scan & Solve now runs on our own secure server - the same one used by OneCalc on Android and Mac - so answers are consistent on every device.
The developer, ANNMAR limited, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Purchases
- User Content
- Identifiers
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- ANNMAR LIMITED
- Size
- 12 MB
- Category
- Utilities
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - Mac
Requires macOS 26.0 or later. - Apple Vision
Requires visionOS 2.0 or later. - Apple Watch
Requires watchOS 11.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- OneCalc Unlock Everything $29.99
- OneCalc Premium Annual $9.99
- Copyright
- © 2026 Pawel Nowak