SafeJSON.dev
JSONLint
JSON-Formatter.app
Code Beautify JSON Validator
betterjson.com
CSVJSON
DomainProtect
ExtendsClass JSON Formatter
assertpy
grappa
SafeJSON is a browser-based JSON toolkit for developers who work with API responses, webhook payloads, JWTs, JSONPath queries, and JSON Schema validation.
It includes JSON formatting, validation, viewing, diffing, JWT decoding, JSONPath querying, and schema validation. Core JSON workflows are designed so pasted content is not intentionally uploaded, and users can verify the boundary in DevTools -> Network.
SafeJSON Pro adds advanced workflows for $5/month or $39/year.
SafeJSON.dev assertpySafeJSON.dev's answer
Safejson runs all JSON processing 100% locally in the user's browser, never uploading any sensitive JSON payloads to external servers. Most competing JSON tools send your confidential data to their backends for parsing, while we guarantee end-to-end client-side privacy alongside a full suite of JSON utilities like diff comparison and JWT decoding.
SafeJSON.dev's answer
Frontend built with vanilla JavaScript + modern browser native APIs for local file handling and parsing, lightweight CSS framework for responsive UI, Lemon Squeezy for subscription & license management, pure client-side JSON parsing libraries with no server-side data persistence.
SafeJSON.dev's answer
Users handling API keys, production secrets or private business data avoid data leakage risks with our local-only processing. We offer the same rich feature set as mainstream JSON tools, but with stronger privacy protection, flexible affordable subscription plans, and device-bound license activation without forced account registration.
SafeJSON.dev's answer
Backend/frontend developers, DevOps engineers, cybersecurity professionals, and indie SaaS builders who regularly work with sensitive JSON data and prioritize data privacy, including enterprise developers dealing with confidential production payloads.
SafeJSON.dev's answer
As a developer, I repeatedly faced anxiety when pasting sensitive API JSON into public online formatters, knowing the data could be logged or leaked on third-party servers. I built SafeJSON to fix this pain point: a fully client-side JSON toolkit that keeps all user data local, while packing all the everyday features developers need, and launched it as an indie MicroSaaS with fair pricing.
SafeJSON.dev's answer
Individual freelance full-stack developers handling client confidential project data Small cybersecurity consultancies auditing API JSON payloads Indie SaaS engineering teams managing internal backend configurations DevOps specialists working with production environment JSON secrets
JSONLint - JSON Lint is a web based validator and reformatter for JSON, a lightweight data-interchange format.
grappa - grappa is an declarative, verbose, and expressive assertion library for Python.
JSON-Formatter.app - json-formatter.app is a free online tool that offers one-click copying, direct file conversion, and downloads. With open-source code and multilingual support, it features JSON beautification and parsing, as well as conversion to other formats like XM
Code Beautify JSON Validator - Code Beautyโs JSON Validator or JSON Lint is easy to use tool to copy, paste and validate JSON data.
betterjson.com - A free, online JSON validator and JSON formatter (or beautifier) that enables users to filter their JSON using JSONPath and share their JSON via generated share links.
CSVJSON - CSVJSON is a textual format for tabular data where each line has zero or more valid JSON values, which are separated by commas.