Free Developer Tools Online: JSON, Base64, Hash, QR & More

Developers reach for small utilities all day: tidy a messy API response, decode a string, generate an ID, test a pattern. Everyone else needs quick converters too, for centimeters to inches, kilograms to pounds, percentages or a birthday. PDFFlowState brings 17 of these together as free developer tools online that open in your browser, work on phone and desktop, and need no sign-up.

Tools for working with data

JSON Formatter and JSON Validator

JSON Formatter formats, minifies and validates JSON. It works as a JSON beautifier when you paste a wall of text and need it readable. JSON Validator finds syntax errors before JSON reaches an API, so you can validate JSON online quickly.

CSV Converter

CSV Converter converts between CSV, JSON and XML, covering searches like JSON to CSV, CSV to JSON and CSV to XML.

Base64 Encode and Decode

Base64 Encode and Decode encodes text to Base64 or decodes it back. It is a quick Base64 encoder and decoder and Base64 decode online tool.

Tools for IDs, hashes and security

Hash Generator

Hash Generator creates MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes. Use it when you need an MD5 generator or a SHA-256 hash online.

UUID Generator

UUID Generator creates random version 4 UUIDs, handy when you generate a UUID online for databases and tests.

Password Generator

Password Generator creates random passwords with your length and character rules, so you can get a strong password in a click.

QR Generator

QR Generator makes QR codes for links, text, WiFi and contacts. It is a free QR code generator for flyers, menus and sharing your WiFi.

Tools for code and design

• Regex Tester tests patterns against sample text, a quick regex tester online.
• Epoch Converter turns Unix epoch into a readable date and back.
• Timestamp Converter converts Unix timestamps and dates.
• PX to REM Converter converts CSS pixels to REM using your root font size.
• HEX to RGB turns color codes into RGB values.
• Color Converter converts between HEX, RGB, HSL, CMYK and HSV.

Everyday calculators and converters

• Unit Converter handles length, weight, temperature, volume and more, such as cm to inches, kg to lbs and mm to inches.
• Percentage Calculator works out percentages and percentage change.
• Age Calculator gives age in years, months and days from a date of birth.

Why use PDFFlowState?

• Free. The tools are offered at no cost.
• No sign-up. Open a tool and use it.
• Works on phone and desktop.
• One place for small jobs, so you do not hunt for a new site each time.

Frequently asked questions

Are these tools free? Yes. Every tool is free and needs no sign-up.

Is there a JSON formatter I can use without installing anything? Yes. JSON Formatter runs in your browser. There is no download or extension to install.

Is Base64 the same as encryption? No. Base64 is an encoding, not a way to keep data secret. Anyone can decode it.

Can I generate bcrypt or Argon2 hashes? Not at the moment. Hash Generator creates MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes.

Can I scan a QR code? Not at the moment. QR Generator creates QR codes, but does not scan them.

Can I convert CSV to Excel or PDF to CSV? Not directly. CSV Converter converts between CSV, JSON and XML, and Extract PDF Text if your data is in a PDF.

Is there a password manager? No. Password Generator creates passwords, but it does not store them.

Start using the free developer tools

Pick a tool from the lists above, or browse them all on the developer and everyday converters page.