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JSON & data

JSON formatter
Format and validate JSON with readable indentation.
JSON diff
Compare two JSON documents by value, including nested fields and array positions.
JSON to CSV
Convert an array of JSON objects into a CSV with a combined header row.
JSON to TypeScript
Generate a TypeScript type from a sample JSON value.
JSON Schema generator
Infer a JSON Schema from a sample document.
JSON Pointer finder
List JSON Pointer paths and values to locate nested response fields.
JSON flattener
Flatten nested JSON into unambiguous JSON Pointer keys.
JSON string escaper
Escape text as a JSON string or decode a quoted JSON string.
NDJSON validator
Validate newline-delimited JSON and report the first invalid line.

CSV to JSON
Convert CSV rows into JSON objects without losing leading zeros.
CSV validator
Find inconsistent columns, broken quotes and duplicate headers, with record numbers and fixes.
CSV duplicate finder
Find repeated complete records in a CSV file.
CSV column extractor
Select and reorder CSV columns by their exact header names.
CSV delimiter converter
Convert comma, semicolon or tab-separated data with correct quoting.
NDJSON to CSV
Convert line-delimited JSON object records into CSV columns.
CSV to NDJSON
Convert each CSV record into one JSON object per line.
HAR viewer
Open a HAR file to inspect requests, headers, captured bodies and timings without uploading it.
HAR sanitiser
Make a HAR copy with headers, query values, bodies and browser metadata removed.

HTTP header parser
Read copied HTTP headers as structured name and value pairs.
cURL command builder
Build a shell-quoted cURL GET command from a URL and headers.
HTTP status code lookup
Look up common HTTP response codes and what to check next.
Content Security Policy parser
Split a Content-Security-Policy header into directives and sources.
Permissions Policy parser
Read Permissions-Policy feature allowlists from a response header.
CORS header checker
Find why CORS blocks a request. Check origins, credentials, OPTIONS status, allowed methods and request headers.
Set-Cookie parser
Inspect cookie names, flags, paths, expiry and SameSite attributes.
Content-Disposition parser
Inspect attachment filenames, including UTF-8 filename* values.
HAR to cURL
Extract a recorded HAR request into a quoted cURL command.

Query string parser
Decode URL parameters while preserving repeated names and blank values.
URL parser
Inspect a URL’s scheme, hostname, port, path, query and fragment.
URL encoder and decoder
Encode a URL component or decode percent-encoded text.
UTM parameter remover
Remove common campaign and click-tracking parameters from a URL.
Base64 encoder and decoder
Encode UTF-8 text as Base64 or decode Base64 back to text.
Base64URL encoder and decoder
Encode and decode the URL-safe Base64 alphabet used by tokens.
HTML entity encoder and decoder
Encode HTML-special characters or decode common and numeric entities as text.
Unicode escape converter
Convert text into JavaScript-style Unicode escapes and decode them.

Basic auth encoder and decoder
Encode a user:password pair or decode a Basic Authorization value locally.
JWT decoder
Read a JWT header, payload and time claims without sending the token away.
SHA hash generator
Calculate SHA-256, SHA-384 or SHA-512 for UTF-8 text.
HMAC generator
Calculate a SHA-256 HMAC of an exact UTF-8 message and secret.
Stripe webhook signature verifier
Debug Stripe-Signature v1 HMACs against the original webhook body.
GitHub webhook signature verifier
Check an X-Hub-Signature-256 value against the exact webhook body.

Unix timestamp converter
Convert Unix seconds or milliseconds to UTC and back.
Time zone converter
Convert an unambiguous date into an IANA time zone.
Time difference calculator
Calculate the elapsed time between two timestamps.
UUID generator
Generate cryptographically random version 4 UUIDs in your browser.
UUID validator
Check UUID text and inspect the version and variant bits.

UTF-8 byte counter
Count UTF-8 bytes, Unicode code points, UTF-16 units and lines.
Text diff
Compare two text blocks line by line using a bounded edit diff.
Duplicate line remover
Remove repeated lines while keeping their first occurrence and original order.
Line sorter
Sort text lines in ascending or descending Unicode code-unit order.
Regular expression tester
Test a JavaScript regex against text with match positions and capture groups.

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