JSON guides & tutorials

Short, practical articles for developers who format, validate, and debug JSON every day. Every guide links back to SparkJSON’s free, 100% client-side tools.

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How to Format JSON Online (Step-by-Step)Learn how to format JSON online in under a minute: paste, indent, validate, and copy — with privacy tips and common mistakes.
How to Validate JSON OnlineValidate JSON online with exact error locations. Learn what “valid JSON” means, how to fix failures, and how SparkJSON checks syntax privately.
Common JSON Errors (and How to Fix Them)Fix the most common JSON errors: trailing commas, single quotes, unquoted keys, comments, and duplicate keys — with examples.
What Is JSON? A Practical Guide for DevelopersJSON explained for working developers: syntax rules, data types, JSON vs XML, and when to format or validate online.
How to Minify JSON (Without Breaking It)Minify JSON safely: validate first, strip whitespace, and keep values intact. Includes when not to minify.
JSON vs XML: Which Should You Use?Compare JSON and XML for APIs and configs: verbosity, tooling, schemas, and real-world defaults for modern web services.
How to Fix Trailing Commas in JSONTrailing commas break strict JSON parsers. Learn why they appear, how to find them, and how to fix them with an online validator.
Duplicate Keys in JSON: Why They’re DangerousDuplicate object keys are legal-ish but unsafe. Learn how parsers resolve them and how SparkJSON warns before data loss.

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