58-format auto-detection
Paste or open data in the browser and let PasteKit detect among 58 listed formats, including structured data, code, configuration files, logs, and query languages.
PasteKit
PasteKit formats, validates, converts, and inspects JSON, YAML, XML, SQL, CSV, code, and more locally in your browser—without sign-up.
Browser-based formatting and data utilities
PasteKit is a browser-based formatter, validator, converter, and inspection toolkit for JSON, YAML, XML, SQL, CSV, code, configuration files, logs, and other text formats. Users paste content into an input pane or open a local file; the tool detects supported formats and produces formatted output in the browser.
Its broader toolset includes JSON comparison, schema validation, repair, path inspection, size and token analysis, table and tree views, spreadsheet conversion, and format conversion. PasteKit states that processing happens in a Web Worker on the user's device and that pasted data is not uploaded to a server, making the tool suited to handling development payloads locally when a browser workflow is appropriate.
Key features
Formatting controls
Beautify, minify, sort keys, wrap lines, choose indentation, copy results, and edit output across the formatter workspace.
In-browser conversion
Convert between supported representations, including JSON, YAML, XML, CSV, TOML, SQL, TypeScript, and several programming-language outputs. The site lists 48 conversion pairs.
Validation and JSON tools
Validate JSON and JSON Schema-related data, compare JSON documents, apply or generate JSON Patch and merge patches, and inspect parser errors with source locations.
JSON inspection and repair
Explore JSON in a collapsible tree, inspect arrays in sortable tables, find JSONPath and related paths, analyze payload size, count tokens, repair common malformed input, and export selected table data.
Browser-local processing
Run parsing and formatting in a browser Web Worker. PasteKit states that data is not sent to a server, and its security page documents a Content Security Policy that limits network connections.
Practical use cases
Inspect API and webhook payloads
Turn compact or difficult-to-read API responses, webhook payloads, and structured logs into indented JSON. Source-located errors and large-number preservation help when inspecting production-like data without changing identifier digits.
Review data changes
Compare two JSON documents by structure, sort object keys for more readable diffs, or generate and apply JSON Patch and merge patches when reviewing changes between payloads.
Check schemas and API data
Validate JSON or YAML against JSON Schema drafts from 04 through 2020-12 or an OpenAPI file, and generate a schema from example data when defining or checking an interface.
Prepare data for another format
Convert structured data between formats such as JSON, YAML, XML, CSV, TOML, SQL, or programming-language representations when preparing configuration, documentation, or code snippets.
Explore and repair JSON
Use Tree, Table, JSONPath, size, token, repair, and spreadsheet tools to explore large or imperfect JSON, identify costly fields, recover common syntax problems, or export records for further work.
Pros and Cons
Pros
- Supports a broad list of 58 formats and 48 conversion pairs.
- Offers more than basic pretty-printing, including validation, comparison, repair, JSON inspection, schema tools, and spreadsheet-related workflows.
- Provides detailed JSON handling, including exact preservation of large integer digits, duplicate-key warnings, source-located errors, Tree view, and Table view.
- Processing is designed to stay in the browser, with Web Worker execution and a published Content Security Policy supporting the stated privacy model.
- No sign-up is required, and the site states that its formatters, converters, and JSON tools are free to use.
Cons
- The tool runs in the browser, so practical file size is bounded by available browser memory; the site specifically notes that sorting keys requires the whole JSON tree in memory.
- The available evidence does not describe collaboration, external integrations, or team workspaces.
- Some specialist operations have narrower behavior; for example, the JWT decoder is described as decode-only unless verification is enabled, and format-specific parsers determine the available validation behavior.
FAQ
Is PasteKit free to use?
Yes. PasteKit states that all 58 formatters, 48 converters, and 16 JSON tools are free to use, with no sign-up and no usage limits beyond what the browser can hold in memory.
Does PasteKit upload or store pasted data?
No. PasteKit says parsing, formatting, validation, and conversion run in a Web Worker in the browser. Its published Content Security Policy restricts network connections, and share content placed after the URL hash is not sent to a server.
How do I use PasteKit?
Paste text into the left pane or open a supported local file, then format it with the interface or the Ctrl/Cmd+Enter shortcut. The tool detects supported formats automatically and displays the result on the right.
Which formats does PasteKit support?
The site lists 58 supported formats, including JSON, JSON5/JSONC, YAML, XML, CSV, TOML, SQL, programming languages, configuration files, logs, queries, and specialist formats such as JWT and regular expressions.
What can the JSON formatter do beyond indentation?
The JSON formatter reports syntax problems with line and column locations, supports beautify and minify modes, preserves large integer digits, and provides Tree and Table views for inspecting JSON.
Quick Facts
- Product type
- Browser-based developer formatting, validation, conversion, and inspection toolkit
- Supported formats
- 58 formats listed by PasteKit
- Conversions
- 48 conversion pairs listed by PasteKit
- JSON tools
- 16 JSON tools listed by PasteKit
- Processing model
- Client-side Web Worker in the browser
- Source domain
- pastekit.dev
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