Build your Percentage Calculator with AI in under 5 minutes
Build a percentage calculator that answers the everyday questions in plain language — what is X% of Y, X is what percent of Y, percentage change, and increase or decrease by a percent — all in the browser.
仕組み
ステップ 1
アイデアを入力
作りたいものを自然な文章で入力してください。
ステップ 2
AIがビルド
FloopFloopが本番対応コードを即座に生成します。
ステップ 3
デプロイして公開
数分以内に専用サブドメインでプロジェクトが公開されます。
開発者を採用する代わりにAIでビルドする理由
| FloopFloop | 従来の開発者 | |
|---|---|---|
| リリースまでの時間 | 5分未満 | 2〜8週間 |
| 費用 | $0から | $5,000〜$50,000以上 |
| メンテナンス | プランに含まれる | 継続的な保守契約 |
What is a percentage calculator?
A percentage calculator handles the small bits of maths that come up constantly but are just annoying enough to want a tool for: working out a tip or a discount, checking what percent of a budget you've spent, figuring a grade, or seeing how much a price changed. The four core questions cover almost everything — what is X% of a number, what percent one number is of another, the percentage change between two values, and a number increased or decreased by a percent. It's among the most-searched calculators on the web precisely because the formulas are easy to forget and easy to get backwards. A good one states each question in plain language, fills in the answer as you type, and is careful about the edge cases — dividing by zero, negative changes, values over 100% — instead of quietly showing a wrong or broken result.
Common features
- What is X% of a number
- X is what percent of Y
- Percentage change between two values (up or down)
- Increase and decrease a value by a percent
- Plain-language, fill-in-the-blank layout
- Live results as you type
- Up/down direction shown for changes
- Safe handling of divide-by-zero (shows a dash)
- Copy any result; everything client-side
- Light and dark themes; inputs remembered
Real-world examples
A discount
Someone works out 25% off a $80 item by reading the 'decreased by' result — $60 — without reaching for a separate calculator.
A grade
A student types 'what percent is 46 of 60' and gets 76.6667% instantly.
A price change
A shopper checks the percentage change from $50 to $75 and sees a green ↑ 50% — and from $100 to $80, a red ↓ 20%.
Why FloopFloop fits percentage calculator projects
A percentage calculator is a tiny tool you want instant, ad-free, and yours. FloopFloop ships the calculator you want — the exact modes you use, VAT or sales-tax presets, your own wording — on your own domain, with every calculation running in the browser. The friendly 'sentence' cards that ship by default state each question in plain English with the answer right there, and the whole thing is one prompt away from being whatever fits your workflow.
試してみてください
以下のプロンプトをコピーしてFloopFloopに貼り付けてお使いください。
Build a percentage calculator with plain-language cards. Card 1: 'What is P% of N?' Card 2: 'X is what percent of Y?' Card 3: 'Percentage change from A to B?' with an up/down arrow and colour. Card 4: a value increased and decreased by P%, showing both. Inline number inputs inside the sentences, results that update live, and a copy button on each. Guard against dividing by zero (show a dash). Keep it deterministic so the first render is hydration-safe, and remember every input in localStorage. 100% client-side.
Create a percentage calculator like the popular ones: type two numbers and get the percent. Cover 'what is X% of Y', 'X is what % of Y', and percentage increase/decrease. Keep it in the browser.
Build a friendly percent calculator for everyday maths — discounts, tips, grade percentages, percentage change — with a clean card layout and a dark theme.
Build a tool to work out percentage change between two numbers, showing whether it went up or down and by how much.
よくある質問
What can it calculate?
How do I work out a percentage of a number?
What's the difference between percentage change and percentage points?
What happens if I divide by zero?
Is anything sent to a server?
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ビルドを始めますか？
今すぐプロジェクトのビルドを開始しましょう — コーディング不要。
Generate this for meビルドを始める