Quick Calc Pad

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  Type calculations in plain words like 20% off 80 and plus 30

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  Rename an answer and every line that uses it updates

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  Typos explain themselves with a one-click Did you mean fix

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  Ready-made templates for VAT, discounts and compound interest

Inspiration

Soulver. I wanted that "type the math in plain words" feel, but free and in any browser, not just a paid app for Mac and iOS.

What it does

You type calculations line by line, like "20% off 80" or "plus 30", and see the answers instantly. Answers get names you can reuse, typos come with a one-click fix, and there are templates for VAT, discounts and compound interest.

How we built it

With Claude Code and the Devpost skill pack: scope, PRD and spec first, then built in small tested slices. It's a single static Astro page in TypeScript, with math.js and GitHub Pages.

Challenges we ran into

math.js reads unknown words as units, so a typo could turn into a strange result. We now catch unknown names first and suggest the closest one.

Accomplishments that we're proud of

It's a full working loop with no server and no sign-up. Renaming an answer updates every line that uses it.

What we learned

Cutting the scope early is what got it finished. Small slices, each one tested and committed, kept it working at every step.

What's next for Quick Calc Pad

Currency and unit conversion, which we deliberately left out of the proof of concept, plus more templates.

Built With

• astro
• css
• github
• github-actions
• html
• localstorage
• math.js
• typescript
• vitest