Every developer task.
One simple place.
JSON, Base64, JWT, regex, UUIDs, and formatters. Local processing, no account required.
What you will find here
Developer tools on SmartKitio target small, local tasks: format or validate JSON, encode or decode Base64 and URLs, inspect JWTs, test regex, generate UUIDs, and look up status codes. Processing stays in the browser whenever the tool can run client-side.
JSON & data
Format, minify, and validate JSON; convert simple tables to and from CSV when the shape fits.
Encoding
Base64 and URL encode/decode for transport and query values—not for secrecy.
Generators & web helpers
UUIDs, passwords, lorem text, hashes, timestamps, and related generators.
Debugging
Regex testing, JWT decode, HTTP status lookup, and similar inspect-only utilities.
Related guides
Read a longer explanation, then return to a tool when you need a result.
- JSON Formatting and Validation: Complete Guide
- JSON vs JSON5: What's the Difference?
- Base64 Encoding Explained
- Base64 Encoding vs Encryption
Related articles
A longer explanation of an idea these tools rely on.
Popular Developer Tools
Our most frequently used tools.
JSON format
Paste compact or messy JSON to pretty-print it with consistent indentation, check that it parses, or minify it back to one line.
Base64 encode
Encode text as Base64 for data URLs, HTTP Basic auth headers, or systems that only accept ASCII.
UUID
Generate random version 4 UUIDs for database keys, test fixtures, or request IDs, up to 50 at a time.
Password
Create a random password of 4 to 128 characters from the character sets you choose. Each password is generated in your browser and is never stored or sent.
JS format
Indent JavaScript using braces and semicolons. Runs locally.
JWT
Paste a JSON Web Token to read its header (algorithm, key ID) and payload claims (subject, expiry, scopes) as formatted JSON.
Regex
Write a JavaScript regular expression, paste sample text, and see every match with its position and capture groups.
Hash
Compute MD5, SHA-1, SHA-256, and SHA-512 digests of text, for example to compare checksums or build test fixtures.
Explore Categories
Find exactly what you need by browsing our organized collections.
All Developer Tools
Browse every developer tool by category, popularity, or name.
Base64 Encoder
Encode text as Base64 for data URLs, HTTP Basic auth headers, or systems that only accept ASCII.
Hash Generator
Compute MD5, SHA-1, SHA-256, and SHA-512 digests of text, for example to compare checksums or build test fixtures.
JavaScript Formatter
Indent JavaScript using braces and semicolons. Runs locally.
JSON Formatter
Paste compact or messy JSON to pretty-print it with consistent indentation, check that it parses, or minify it back to one line.
JWT Decoder
Paste a JSON Web Token to read its header (algorithm, key ID) and payload claims (subject, expiry, scopes) as formatted JSON.
Password Generator
Create a random password of 4 to 128 characters from the character sets you choose. Each password is generated in your browser and is never stored or sent.
Regex Tester
Write a JavaScript regular expression, paste sample text, and see every match with its position and capture groups.
UUID Generator
Generate random version 4 UUIDs for database keys, test fixtures, or request IDs, up to 50 at a time.
Base64 Decoder
Decode a Base64 string back to readable text, for example to inspect an encoded config value or email header.
Color Converter
Convert hex and rgb() colors to hex, RGB, and HSL.
CSS Formatter
Indent CSS rules and declarations locally.
CSS Minifier
Strip comments and extra whitespace from CSS locally.
CSV to JSON
Convert a CSV export with a header row into a JSON array of objects, ready for code, fixtures, or APIs.
HTML Decoder
Turn HTML entities back into readable characters, for example text copied from page source or an RSS feed.
HTML Encoder
Escape text so it displays literally inside HTML, for example to show a code sample on a web page.
HTML Formatter
Indent HTML tags for readability. Processing stays in the browser.
HTTP Status Code Lookup
Search common HTTP status codes by number or name, and see what each response class means for browsers, APIs, and search engines.
JavaScript Minifier
Remove comments and extra whitespace from JavaScript locally.
JSON Minifier
Remove whitespace from valid JSON without changing the data.
JSON to CSV
Turn a JSON array of objects, such as an API response, into a CSV table you can open in a spreadsheet.
JSON Validator
Check whether text is valid JSON and see the parser error if it is not.
Lorem Ipsum Generator
Generate placeholder paragraphs for layouts and mockups.
MIME Type Lookup
Find the correct Content-Type header for a file extension, or the extension for a MIME type, from a list of common web formats.
Unix Timestamp Converter
Convert Unix epoch timestamps to readable UTC dates, or convert a date back to a Unix timestamp in seconds.
URL Decoder
Turn percent-encoded URLs and query strings back into readable text, for example to inspect tracking links or redirect parameters.
URL Encoder
Percent-encode a value so it can be placed safely in a query string or URL path segment.
User-Agent Parser
Paste a User-Agent string to extract a browser version token, a rendering-engine guess, the first OS fragment in the parentheses, and whether the string looks mobile.