Format, validate and convert JSON, YAML, CSV and TypeScript
Everything here runs in your browser. Files are never uploaded.Most data a developer touches in a day is JSON, or needs to become JSON: an API response to read, a YAML config to check, a spreadsheet export to load, a payload that needs a type. These tools cover that loop, show exactly where input breaks, and run entirely in your browser, so production payloads with keys and customer data never leave your machine.
JSON Formatter indents, validates, sorts and minifies, and reports the line and column of the first error with a plain-English fix. JSON Diff compares two documents by structure rather than by line, so a reordered object is correctly reported as no change at all, which is the thing a text diff always gets wrong about JSON.
YAML to JSON and CSV to JSON work in both directions. YAML anchors are resolved, CSV delimiters are detected, and nested JSON is flattened with dotted keys when it becomes CSV. Data Converter widens that to XML, TSV, TOML and INI, for the config file that has to change shape because the tool reading it did.
JSON to TypeScript writes interfaces from a sample, merging array elements so optional fields are marked optional instead of guessed.
Base64 encodes and decodes text and files, including data URIs for images.
Pasting a production payload into a site that posts it to a server is a leak. Nothing here makes a network request with your input.
No. Parsing and conversion run in your browser. Nothing you paste leaves your device.
Several megabytes format in well under a second. The limit is your browser memory.
No. JSON has no comments, so they are dropped. Anchors and aliases are resolved into full values.
They are flattened into dotted column names such as address.city, and the tool warns you when that happens.
Yes, with no account and no limits.