Compute rectangle area and perimeter from length and width — flooring, paint, fencing estimates. A 12×15 ft room needs 180 sq ft of flooring — free, runs locally.
Content reviewed October 2026 · About Toolzum
Compute circle area and circumference from the radius — geometry homework solved. Enter r=5 and read both measures at once — free, local, no signup.
Compute display DPI from pixel width, pixel height, and diagonal inches — diagonal pixels over diagonal size. Compare phone and laptop sharpness honestly — free, runs locally.
Compute test percentages and grades from correct/total with curve options. Turn 42/50 into 84% (B) instantly — free, local, no signup.
Convert between hundreds of units — length, mass, volume, temperature, area, speed, time, digital data, and more with a single click.
Build bar, line, pie, doughnut, area, and horizontal-bar charts from a label/value table (minimum 2 rows) with 10 ten-color palettes, title/axis labels, background, and labels/legend toggles. Canvas renders at device-pixel-ratio sharpness, width 400–2000px, height 300–1200px — exports PNG named after your title.
180 sq ft (12×15) — add 10% waste for cuts: order 198 sq ft. The tool shows area with perimeter for baseboard math in the same pass.
Area for covering (paint, tile, sod); perimeter for edging (fencing, trim). Both display together so one entry serves both errands.
Square units of whatever you entered — feet in, square feet out. Keep both inputs in the same unit; mixing feet and inches silently corrupts the result.
No — math runs locally in your browser. Dimensions never leave your device.
Percentage Calculator
Computes X% of Y and what-percent-of-what (X is what % of Y) in two side-by-side panels with precise decimal arithmetic. Essential for everyday math — tips, discounts, tax rates, grade scores, and statistical comparisons where quick percentage answers are needed.
Age Calculator
Computes exact age in years, months, and days from a given birth date relative to any target date. Numbers never leave your device — every calculation runs locally in your browser.
ETA Calculator
Estimate travel time from distance and speed — with optional arrival time and traffic buffer. Add traffic buffers and arrival targets for realistic plans — free, local, no signup.
Study Time Calculator
Plan study hours from syllabus weight and days left — pass with scheduled effort. Turn 5 chapters in 10 days into daily targets — free, local, no signup.
Test Score Calculator
Compute test percentages and grades from correct/total with curve options. Turn 42/50 into 84% (B) instantly — free, local, no signup.
Words Per Page Calculator
Estimate pages from word count and font size — about 500 words/page at 12pt, 600 at 10pt and under. Font-size-only math, no spacing or margin inputs — free, local, no signup.