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405+ 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 category below.
Total tools405Available free tools
Categories15Active categories
Most usedCSV to ExcelPopular right now
Recently addedInterval Music RepeaterNewest tool
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text instantly in your browser.
Mean Median Mode Calculator
Find the mean, median, and mode of any data set with frequency tables, sorted data, and step-by-step work.
Half-Life Calculator
Calculate radioactive decay with half-life — remaining amount, elapsed time, or half-life from N = N₀(½)^(t/t½). Free, instant, browser-based.
Genetic Probability Calculator
Calculate offspring genotype and phenotype probabilities from Punnett squares — monohybrid and dihybrid crosses with instant results. Free, browser-based.
Curl Converter
Convert curl commands into JavaScript fetch, Axios, Python requests, Go, PHP, and PowerShell code.
Pitch Speed Changer
Free online pitch and speed changer — slow down, speed up, or shift pitch of any audio file in your browser. Private, no upload, no signup.
HTTP Header Checker
Inspect HTTP response headers for any URL. Review security headers, caching directives, CORS, and server metadata.
JSON to CSV
Convert JSON arrays of objects to CSV with configurable delimiters and nested field flattening.
RSA Encrypt
Encrypt and decrypt text with RSA-OAEP public/private keys, including hybrid mode for longer messages.
PDF to JPG
Convert PDF pages to JPG images in your browser with adjustable quality and resolution.
DNS Lookup
Query public DNS records for any domain — A, AAAA, MX, TXT, NS, CNAME, SOA, SRV, CAA, and PTR.