Your all-in-one free online toolbox
Developer, image and PDF tools that run entirely in your browser. Your files and data are never uploaded — privacy by design.
- 100%
- Client-side
- 10+
- Free tools
- $0
- Cost
- 2
- Languages
Why OmniTool?
Built for speed, privacy and zero cost.
Privacy by design
Every tool runs 100% in your browser. Your files and data never leave your device.
Instant & free
No uploads, no waiting, no accounts, no hidden fees. Process files locally at full speed.
Zero cost forever
Static pages on free hosting mean the service costs us nothing — so it is free for you.
Works on any device
Responsive and lightweight. Use it from your desktop, tablet or phone.
All tools
Pick a category to get started. Everything runs locally in your browser.
Developer Tools
JSON Formatter
Format, validate and minify JSON in your browser. No data is ever uploaded.
JSON Diff
Compare two JSON documents side by side and see differences instantly.
JWT Decoder
Decode JWT tokens, inspect the header and payload, and verify signatures.
Base64 Encoder/Decoder
Encode text or files to Base64, or decode Base64 back to readable text.
Hash Generator
Generate SHA-1/256/384/512 and MD5 hashes using your browser Web Crypto.
UUID Generator
Generate cryptographically secure random UUID v4 / GUID values in bulk.
Chinese to Pinyin
Convert Chinese characters to pinyin with automatic polyphonic disambiguation.
Cron Expression Parser
Parse cron expressions into a human-readable schedule with next run times.
Network Tools
URL Encoder / Decoder
Encode or decode URLs and URL components with configurable options.
Subnet / CIDR Calculator
Compute network, broadcast, mask and host ranges from any CIDR block.
HTTP Status Codes
Look up the meaning of any HTTP status code, grouped by class.
Common Ports Lookup
Find the service behind well-known TCP and UDP ports.
IP Address Converter
Validate IPv4/IPv6 addresses and convert between decimal, binary and hex.
Time & Date
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates, in seconds or milliseconds.
Date Formatter
Format any date with common presets or your own YYYY-MM-DD template.
Time Zone Converter
Convert a time between any two time zones and see multiple world clocks at once.
Date Difference Calculator
Calculate the exact difference between two dates in years, months and days.
Relative Time Converter
Turn a date into friendly relative time like "3 hours ago" or "in 2 days".
Image & Media
PDF & Documents
Frequently asked questions
Are my files uploaded to a server?
No. Every tool processes data locally in your browser using JavaScript, Canvas and Web Crypto. Nothing is ever sent to our servers.
Is OmniTool really free?
Yes. The site is a static page hosted on a free tier, so there is no cost to us and no charge to you. Ads keep it running.
Which browsers are supported?
All modern browsers — Chrome, Edge, Firefox and Safari. Tools that use Web Crypto require HTTPS, which we provide by default.
Is there a file size limit?
The only limit is your device memory. Large PDFs and images are processed in chunks when possible.