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Calculators

Quick everyday calculators — keep an aspect ratio when resizing images or video, and solve common percentage problems.

6 tools · 100% client-side · nothing is uploaded

📐Aspect Ratio

Keep an aspect ratio when resizing: enter the original size and one new dimension to get the other. Free, in your browser.

%Percentage

Calculate X% of Y, what percent X is of Y, and percentage increase or decrease between two numbers. Free online.

🎓GPA

Calculate your GPA from course grades and credit hours on the 4.0 scale. Add as many courses as you need. Free online.

🕐Hours

Calculate hours and minutes worked between a start and end time, minus breaks. Free online time card calculator.

➗Fraction

Convert a fraction to a decimal and percentage instantly. Free online fraction to decimal calculator.

🧮Ratio

Solve a proportion A:B = C:D for the missing value. Free online ratio and proportion calculator.
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Privacy: every tool in this category runs entirely in your browser. Your input is never sent to, received by, or stored on any server — no uploads, no tracking.