Developer tools

Validate, encode and prepare your data.

URL query parameter parser

Extract parameters from a URL or query string as JSON name/value pairs.

Number base converter

Convert integers between binary, decimal, hexadecimal and bases from 2 to 36.

CSV to JSON

Convert a CSV table to a JSON array using the first row as column names.

JSON to CSV

Convert a JSON array of objects to a downloadable CSV table.

JSON formatter and validator

Validate JSON and add indentation to make it easier to read.

JSON minifier

Validate JSON and remove formatting whitespace.

Base64 encoder and decoder

Encode UTF-8 text as Base64 and decode valid Base64.

URL encoder and decoder

Encode text for a URL or decode percent-encoded characters.

HTML entity encoder and decoder

Convert HTML special characters to entities and back.

UUID v4 generator

Generate UUID v4 identifiers with cryptographic randomness.

SHA-256 hash generator

Calculate the SHA-256 hash of UTF-8 text in your browser.

Validate data and choose a representation

Each format has different rules. Keep a copy before converting and check the receiving program’s needs: data types, delimiter, encoding and structure.

Read and validate JSON

Checks syntax and adds indentation. It does not validate a schema or retain every original numeric representation.

JSON formatter and validator →

Import a table

Headers become keys and cells remain text, including leading zeros.

CSV to JSON →

Export objects as a table

Includes all keys found. Nested data is stored as JSON inside a cell.

JSON to CSV →

Represent UTF-8 text in Base64

Uses standard Base64 with padding. This is a reversible encoding.

Base64 encoder and decoder →

Paste file contents into the corresponding field; CSV and JSON are not loaded through a file picker. Very large JSON numbers may lose precision and duplicate keys retain the last value.

Your files are processed here, on your device

We do not send your file or text contents to a processing server. No account is needed and there is no daily operation quota. Individual tools have size limits to protect your device’s memory.

A connection is needed to load the site and its resources. Hosting may receive technical visit data. Favorites store only tool identifiers in this browser.

How we handle your data →