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Math
Use free online math calculators for percentages, fractions, statistics, geometry, equations, number tools, grades, and date calculations.
Finance
Plan loans, savings, investments, salaries, taxes, retirement, budgets, interest, and mortgage payments with free finance calculators.
Health
Calculate BMI, calories, macros, heart rate zones, pregnancy dates, hydration, fitness metrics, body composition, and wellness estimates.
Converters
Convert length, weight, temperature, area, volume, speed, time, energy, data storage, and other common measurement units online.
Date & Time
Free date and time tools to convert Unix timestamps, calculate the difference between dates, count down to a deadline, switch time zones, and convert military time.
Everyday
Practical everyday calculators for paint coverage, concrete and gravel volumes, electricity costs, wind chill, heat index, fuel cost, ABV, and more.
Developer Tools
Free online developer tools including JSON formatters, encoders, converters, validators, generators, regex testers, and debugging utilities. No signup, runs in your browser.
Data Tools
Free online data tools to convert between CSV, JSON, XML, YAML, Excel and TSV, clean messy CSVs, sort and de-duplicate rows, and merge or split columns.
Text Tools
Free online text tools to count words and characters, change case, remove duplicate lines, compare or diff text, reverse strings, and convert between binary, Morse and fancy Unicode text.
Writing Tools
Free writing tools to summarise text, paraphrase, check grammar, generate outlines and FAQs, estimate reading time, and produce Markdown previews.
PDF Tools
Browser-based PDF tools to merge, split, rotate, compress, unlock, convert PDFs to JPG, Word or Excel, add page numbers, and inspect metadata. Free, no upload.
Image Tools
Free browser-based image tools to compress, convert, resize, blur, remove backgrounds, extract dominant colours, and turn images into Base64 or PDF. Nothing leaves your device.
Design Tools
Free design tools for picking colours, generating palettes and gradients, checking WCAG contrast, building CSS shadows and border-radius, and calculating aspect ratios.
SEO Tools
Free online SEO tools for keyword density, meta tag generation and analysis, blog and YouTube title ideas, slug generation, and structured data helpers.
Social Media Tools
Free social media tools to generate Instagram and Twitter bios, captions and hashtags, create usernames, and produce platform-ready content quickly.
Security Tools
Free security tools to generate strong passwords, score password strength, hash text with MD5/SHA, decode JWTs, calculate chmod values, and clean tracking parameters from URLs.
Web Tools
Free web tools to check your public IP, scan QR codes, test internet speed, inspect HTTP headers, check website status, and detect user agents.
File Tools
Free file utility tools to convert audio and video formats, clean and rename messy file names, and check or convert file sizes without uploading anything.
Fun
Fun online tools and random generators including a spin wheel, dice roller, coin flip, Would You Rather and Truth or Dare prompts, love calculator, and compliment generator.
All Tools
Browse every BlinkCalc tool in one searchable, filterable index.