Everyday calculators
Practical tools for dining, school planning, and comparing car fuel labels across regions—all run locally in the browser.
Tools in this category
- Tip calculator — gratuity, total with tip, per-person split.
- GPA calculator — weighted 4.0-scale GPA from grades and credits.
- Fuel economy converter — US MPG, L/100 km, km/L.
Examples
$86 check, 18% tip, 4 people → about $25.37 each with tip. Courses A (3 cr), B+ (4 cr), A− (3 cr) → weighted GPA near 3.6 on a 4.0 map. 30 US MPG → about 7.8 L/100 km.
Frequently asked questions
How much is 18% tip on a $100 bill?
18% of $100 = $18 tip, $118 total with tip. Use the tip calculator—enter 100, tap 18%, or try preset shortcuts for common bills.
How do I split a restaurant bill with tip between 4 people?
Calculate total with tip, then divide by headcount. Example: $86 bill + 18% ≈ $101.48 ÷ 4 ≈ $25.37 each on the tip calculator (bill, rate, party size).
Should I tip on tax or on the subtotal?
Both customs exist: subtotal × tip% before tax, or full check × tip%. Pick one rule and enter that dollar amount in the bill field on the tip calculator every time.
How do you calculate weighted GPA on a 4.0 scale?
GPA = Σ(grade points × credits) ÷ Σ(credits). Example: 3 cr A (4.0) + 4 cr B+ (3.3) + 3 cr A− (3.7) → 36.3 points ÷ 10 cr = 3.63 on the GPA calculator.
What GPA is a B+? What is 3.5 GPA in letter grades?
On this site’s table, B+ = 3.3 points per credit before weighting. A 3.5 GPA is often between B+ and A− depending on the mix—model your courses on the GPA calculator.
Is CalcTool GPA official for college applications?
No—planning and sanity-check only. Transcripts use your school’s scale (weighted/unweighted, +/- rules). Confirm mappings in your student handbook before submitting applications.
How do I convert 30 MPG to L/100 km?
US formula: L/100 km ≈ 235.2 ÷ MPG. 30 MPG ≈ 7.84 L/100 km. Enter 30 on the fuel economy converter (MPG US → L/100 km) or use the 30 MPG shortcut.
MPG vs L/100 km—which number means better fuel economy?
For US MPG and km/L, higher is better. For L/100 km, lower is better. The fuel converter switches units so you can compare US window stickers with European labels.
Is US MPG the same as UK MPG?
No—UK imperial gallons are larger, so UK MPG reads higher for the same car. CalcTool’s fuel economy converter uses US MPG only; convert European L/100 km instead of assuming UK MPG.
Can I convert electric MPGe or kWh/100 km here?
Not on the gasoline/diesel fuel economy converter. EV efficiency needs MPGe or kWh/100 km tools. For trip distance in miles or km, use the length converter on the units hub.