Everyday Calculators

Practical calculators for daily life: tipping, splitting bills, discounts, and percent off sale prices.

Calculators in this category

About everyday calculators

Everyday calculators cover the routine math of restaurants, shopping, and quick household decisions. They're the tools you reach for at the checkout, at dinner, or when comparing a coupon to a sale price. Every page shows the formula and a worked example so the answer is easy to defend if your dining companions disagree.

The Tip calculator handles bill splits, custom percentages, preset 10–25% buttons, a full tip table, and a round-up toggle. The Percent Off calculator finds sale prices, savings, reverse original prices, and stacked-discount totals — and optionally adds sales tax.

Bookmark this category for the calculators you'll use most often. All tools work offline once the page has loaded.

Popular everyday tools

Frequently asked questions

Do I tip on the pre-tax or post-tax bill?

Convention in the U.S. is to tip on the pre-tax subtotal, but many people tip on the round total. The Tip calculator lets you decide which amount to enter.

How do stacked discounts work?

Stacked discounts apply one after another, not added. 20% off then 10% off is 1 − (0.8 × 0.9) = 28%, not 30%. The Percent Off calculator computes stacked totals correctly.

Are tipping customs the same everywhere?

No. 15–20% is standard in the U.S., but other countries have lower expectations or include service automatically. Check local norms before traveling.

Do these calculators work offline?

Once the page has loaded, the math runs entirely in your browser and works without an internet connection.