PrefixCalc vs DIGITCA

This calculator supports Metric‑prefix such as kilo and giga. The calculator supports quetta (10^30) and quecto (10^-30), which were added in 2022. Main Functions ・Support for arithmetic operations (+ - ×÷) ・Results converted to Japanese numerals for display ・Delete one character at a time with the "DEL" button 　Press and hold to delete all ・Press and hold to copy calculation formulas and results 　English (Short scale, Long scale) and 　Chinese numerals can also be selected. ・Calculations that include prefixes such as 2M+1k, 2M×1μ, etc. Note: ・Very large numbers that exceed 200 digits may be rounded off for display and calculation purposes. 　Please note this when precision is required. ・Short scale and Long scale are currently supported up to 10^198. ・Kanji notation is supported up to 10^72. 　If it is greater than the number, it will be displayed in Arabic numerals.

A tape calculator that doesn't forget. Every number you tap goes onto a tape you can scroll, edit, save, and come back to. No more wiping the screen by accident and losing the whole calculation. No more squinting at one line of digits, trying to remember what you were even working on. DIGITCA is built around a simple idea: numbers deserve a paper trail. The tape isn't just a log. It's the calculator itself. Tap any number to change it on the spot and watch the totals update live. Strike a row out like a pencil would. Undo anything: a deleted row, an edit, even a cleared tape, with a button, a shake, or a three-finger swipe. Autosave keeps your work safe between sessions. FREE Full tape calculator: persistent, scrollable, autosaved, with full undo Editable tape: tap any number to change it and totals recalculate instantly Tape order your way: authentic (newest at the bottom) or modern Cashier mode for quick running totals Scientific keyboard: trig, log, factorial, combinations, permutations, scientific notation, and statistics computed over your actual tape Natural input: type or dictate "twelve fifty plus tax" and DIGITCA gets it. On Apple Intelligence iPhones, an on-device language model catches phrasing the parser can't Date and time math: add days to a date, subtract weeks, calculate durations Currency converter: 161 world currencies + major crypto, rates from open.er-api.com Unit converter: length, weight, temperature, volume, speed, and more Live totals in the Dynamic Island while you calculate Plain text export Default light and dark themes Interactive Home Screen widget Speaks 11 languages, starting in yours DIGITCA FULL Tape archive: name, browse, search, tag, and reload past sessions, synced through your own iCloud, locked behind Face ID or PIN if you want Share tapes as encrypted .digitca files that preview right in the Files app Palettes inspired by classic calculator design: Braun-style, Pixel Art, Blueprint, Swiss, and more Tactile sounds inspired by classic calculators Full export suite: thermal card, PDF, CSV, Markdown, and 9:16 video for Reels and Stories More visual customisation: custom app icon, numeric font packs, tape density, custom logo on exports One-time purchase. Family Sharing supported. INTERACTIVE HOME SCREEN WIDGET Pin a live currency converter to your Home Screen. Tap to swap currencies, switch between preset amounts, and see the unit rate and last update time at a glance. NO SUBSCRIPTIONS. NO ADS. NO TRACKING. Your tapes live on your device and sync only through your own iCloud. We have no servers, no accounts, and no idea what you calculate. For shopkeepers, accountants, cooks, freelancers, designers, students, and anyone who runs the same numbers more than once and wants to remember how they got there. Made in Brevnov, Prague.