Free Online Tools

184+ free online tools for PDF, images, SEO, developers, color, and productivity. Fast, browser-based, and private — no signup, no installs, no limits. Search above or browse by collection below.

Total tools18410.7K total uses

Categories11Active categories

Most usedJSON Formatter4.1K uses

Recently addedElectron Configuration GeneratorNewest tool

Scientific Tools

Blood Type Inheritance Calculator

Predict child blood types from parent ABO and Rh types — Punnett squares, probabilities, and combined outcomes like A+ or O−. Free, instant, browser-based.

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Scientific Tools

Phylogenetic Tree Generator

Build phylogenetic trees from distance matrices, aligned DNA sequences (UPGMA), or Newick strings — SVG diagram, ASCII tree, and export. Free, browser-based.

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Scientific Tools

Mutation Simulator

Simulate DNA/RNA mutations — substitutions, insertions, deletions, and seeded random SNPs with highlighted output and mutation log. Free, browser-based.

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Scientific Tools

Microscope Magnification Calculator

Calculate microscope total magnification, field of view from FN, and actual specimen size from image measurements — eyepiece × objective. Free, browser-based.

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