Free 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.
Choose a tool and get an instant result
BlinkCalc tools are designed to be fast, practical, privacy-conscious, and easy to understand. Every result is calculated in your browser.
File Name Cleaner
Clean, sanitize, and normalize messy file names.
File Size Calculator
Convert file sizes between Bytes, KB, MB, GB, and TB using the binary 1024-byte system.
MP4 ↔ MP3 Converter
Extract MP3 audio from MP4 video, or wrap an MP3 into an MP4 container.
Related categories
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.
Frequently asked questions
Are these file tools really free?
Yes. Renaming, sizing, and converting files all run free, in your browser, with no signup.
Do you upload my files?
No. Every file tool runs locally. Your files never leave your device.
How large a file can I process?
The practical limit is your device's memory. Multi-gigabyte files may need a desktop tool; everything smaller works comfortably.