JSON, CSV and developer tools online

Validate or convert JSON and CSV, inspect URLs, and generate UUIDs or hashes. Review types, precision, encodings and limits before integrating output.

JSON to Markdown table

Convert a JSON object array into a copyable Markdown table.

Change CSV delimiter

Convert tables between commas, semicolons and tabs while retaining values.

File SHA-256 checksum

Compute a file SHA-256 checksum locally without uploading it.

Text to binary and binary to text

Convert UTF-8 text to eight-bit binary bytes and back.

JSON Pointer lookup

Extract a JSON value using a JSON Pointer path.

Compare JSON

Compare JSON values and locate added, removed or changed members.

URL builder

Add query parameters and a fragment without encoding them by hand.

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.

JWT decoder

Read the header and payload of a JWT in your browser without sending it to any server.

Escape and unescape strings

Escape or unescape text for JSON, JavaScript or regular expressions.

Sort JSON keys

Recursively sort JSON object keys while preserving array order.

Flatten JSON

Turn nested JSON into a JSON Pointer path map preserving values and empty containers.

CSV to Markdown table

Convert CSV or TSV into a Markdown table with headers, alignment and escaped characters.

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.

Distinguish data, representations and identifiers before choosing an operation. JSON and CSV describe different structures, Base64 represents bytes as text, URL encoding handles component representation, UUID creates random references, and SHA-256 summarizes existing content. These functions are not interchangeable. Prepare a small sample matching the receiver’s expected format and test a round trip where appropriate. Knowing what is being transformed is essential to interpreting output instead of merely accepting a valid looking string.

Syntax validation does not establish an application schema. A JSON document can parse while containing incorrect types; a table can lose context around empty cells or nested data. Large numbers, repeated keys, leading zeros and delimiters deserve explicit review. Keep the original when an exchange depends on exact bytes. State encoding variant and character set for transformed strings, avoiding repeated conversions without knowing their current representation. Verify output in the destination with suitable fictitious data before integration. Tools process locally, but publishing a copied result still exposes its content; removing secrets from examples is a decision to make before sharing. A successful conversion should preserve the information the receiving workflow actually needs.

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.

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How we handle your data →