Simplify any two-number ratio to lowest terms via GCD — paint mixes, screen sizes, shares. Reduce 150:225 to 2:3 in one pass — free, runs locally.
Content reviewed October 2026 · About Toolzum
Find the greatest common factor (GCF/GCD) of number sets via Euclidean algorithm with steps. Reduce 48:180 to 4:15 correctly — free, local, no signup.
Convert screen sizes between inches, cm, resolution, and aspect — compare displays honestly. Check a 27-inch 4K pixel density — free, local, no signup.
Get any image or screen's aspect ratio in reduced form with common-ratio matching — 16:9, 4:3, 1:1 and custom. Check a 1920×1080 screen reads 16:9 — free, runs locally.
Stamp headers and footers on every PDF page — page numbers, dates, confidentiality lines. Number a 100-page report in one pass — local pdf-lib work, unlimited saves.
Resize one animated GIF to exact dimensions via FFmpeg Lanczos (default), Bilinear, or Nearest — width presets 100/150/200/320/480/640px or custom, height auto-follows with aspect lock ON (unlock to stretch). W/H prefill from the source; saves as <name>-resized.gif with animation intact.
No — this tool simplifies two-number ratios only: no totals, no three-part splits. Simplify here first, then divide by hand (parts sum to the divisor, each share = total ÷ parts sum).
Divide by the greatest common divisor (75): 150:225 simplifies to 2:3. Simplified ratios mix paint and share profits without rounding drift.
A ratio compares parts (2:3); a fraction takes part over whole (2/5). The tool shows the reduced ratio only — read part-over-whole fractions off it yourself.
No — all computation runs locally in your browser. Nothing leaves your device.
Proportion Calculator
Solve proportions a/b = c/d for the fourth term — recipes, maps, dosages scale correctly. Double a 4-serving recipe to 10 without breaking ratios — free, runs locally.
Fraction Calculator
Add, subtract, multiply, and divide fractions with simplification and decimal equivalents. Split 3/4 of a bill three ways without decimal drift — free, runs locally.