Voice input

Click the button, say a math problem like "twenty plus seven" or "fifteen minus four", and watch the number-word parser turn it into digits and run it through the expression grammar.

Try "twenty plus seven" or "fifteen minus four"

The iOS app uses Apple's on-device Speech framework — your browser uses the Web Speech API, which may route audio to a remote service depending on the vendor. The number-word parser is identical: same synonyms (plus / add / minus / take / less), same homophones (ate → 8), same filler-word stripping.