Prism Tape Calculator

Prism Tape Calculator is a calculator with a paper tape. Every line you enter is printed above the keys, the answer updates as you type, and you can tap any earlier result to use it again — with no ads, no tracking and no subscription.

THE TAPE
• Every calculation you commit is printed to the tape, newest at the bottom, like an adding machine.
• The last few lines stay visible above the display, so you always have context.
• Tap any line to drop its result into what you are typing now.
• Open the full tape to scroll back through everything, swipe to delete a line, or clear it all.
• The tape is stored on your device and is there when you come back.

SEE THE WHOLE EXPRESSION
• The full expression stays on screen — 1,250 × (1 + 8.25%) — not one number at a time.
• The result previews live under it before you press equals, so typos are caught before they cost you.
• Backspace removes one key at a time (a whole function like sin( in one go).
• Press an operator after equals to keep going from the last answer; ans is always a key away.

MATH YOU CAN TRUST
• Decimal arithmetic: 0.1 + 0.2 = 0.3, exactly. Money math without floating-point surprises.
• Percent that behaves the way people mean it: 200 + 15% = 230, 50 − 10% = 45, 20 × 5% = 1.
• Thousands separators, sensible rounding, and scientific notation only when a number really needs it.
• Clear error messages instead of a mystery “Error”: divide by zero, unbalanced parentheses, invalid input.

SCIENTIFIC WHEN YOU NEED IT
• Tap sci (or rotate to landscape) for parentheses, powers, roots, sin, cos, tan, ln, log, factorial, π and e.
• Degrees or radians. Implicit multiplication works: 2π and 3(4 + 1) mean what you expect.

DESIGNED FOR THE PHONE IN YOUR HAND
• Big rounded keys sized to your screen, haptic feedback, light and dark mode.
• The whole app is a few megabytes and opens instantly. Works completely offline.
• VoiceOver reads the expression and every tape line. Supports Dynamic Type.

PRIVATE BY DESIGN
• No ads. Ever.
• No account, nothing to sign in to.
• No analytics, no advertising SDKs, no third-party code.
• Nothing leaves your device.

Prism Tape Calculator is free and fully unlocked, made by Prism Data Group.

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Support: https://prismdatagroup.com/prismtapecalculator/support
Privacy Policy: https://prismdatagroup.com/prismtapecalculator/privacy
Terms of Use (Apple Standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/