See it in action
A clean, editable tape — on your phone or tablet.
Write your calculation like notes. Every line stays visible and editable — change any number and the totals update instantly.
No more "did I type that right?". Check your work, fix any line, and keep going.
Correct any number in place — every following total recalculates automatically.
Name each line (e.g. "Rent 650") so your calculation reads like notes.
Type 650 + 10% or 500 − 30% — it just works.
Separate tapes for work, budget, and shopping. Everything is saved.
Undo/Redo and memory keys (M+, M−, MR, MC), like a real calculator.
Light, Dark, and System themes. Comfortable on phones and tablets.
A clean, editable tape — on your phone or tablet.
Enter numbers and operators like you'd jot them on paper.
Tag any line so you remember what each figure is.
Change a number anywhere — totals update instantly.
Copy or share your whole tape, formatted and clear.
A tape calculator (also called an adding machine) keeps every entry visible on a running tape, like the paper roll on an office calculator. ArithCalc lets you edit any line and the totals recalculate instantly.
Yes. ArithCalc is free to download, works fully offline, and requires no account.
Yes. Tap any line, change the number, and every total below updates automatically.
Yes. Type expressions like 650 + 10% or 500 - 30% directly in the tape.
Yes. ArithCalc works on phones and tablets, in both portrait and landscape.
No. Your calculations are stored only on your device and are never uploaded. ArithCalc collects no personal data that identifies you — only anonymous, aggregated analytics to improve the app.
No account needed. Your calculations stay on your device — we only use anonymous analytics to improve the app.