Delta: Percentage Calculator

Delta is a fast, focused percentage calculator for the numbers you actually run into — a price change, a sale tag, a tip, a raise, a savings plan. Type two numbers and the answer appears instantly. No ads, no account, no internet required. WHAT YOU CAN WORK OUT • Percentage change — the change from one value to another, with the increase or decrease shown clearly and charted • Projection — apply a percentage to any amount to see where it lands, for growth or decline • Discount — what a sale price really costs and how much you save • Markup & margin — turn a cost price into a selling price • % of total — what share one number is of another • Compound growth — model savings and investments over years, including regular contributions • Tip & split — the tip, the total, and what each person owes BUILT TO BE QUICK • Results update live as you type • Preset shortcuts for common percentages • Swap your two values with one tap • Save any calculation to history and reuse it later • Share a result as a clean image • Works completely offline MADE TO LOOK GOOD • Full dark mode and light mode • Choose your currency symbol, or turn it off • Clear typography built for reading numbers DELTA PRO Delta Pro unlocks compound growth, tip & split, accent colour themes, and CSV export of your history. Choose a yearly subscription, or pay once for lifetime access and keep it without any recurring charge.