JSON Concepts & Fundamentals

What JSON is, its data types, and how it works across JavaScript, Python, and Node.js.

·8 min read

JSON Number Precision: Why 0.1 + 0.2 Isn't 0.3

JSON has one number type and no precision rules — so parsers use IEEE 754 doubles. Where floating-point rounding and the 2^53 integer limit bite, and how to store money and IDs safely.

·8 min read

JSON Import Attributes: import data from './x.json' with { type: 'json' }

ES2025 standardized importing JSON modules with the `with { type: 'json' }` syntax. How it works, why the type attribute is required, dynamic imports, and the security reason behind it.

·8 min read

Deep Clone in JavaScript: structuredClone vs JSON.parse(JSON.stringify)

The classic JSON.parse(JSON.stringify(obj)) clone silently drops dates, undefined, functions, and crashes on cycles. structuredClone is the native fix — here's exactly what each handles.

·9 min read

JSON.stringify() in JavaScript — Complete Guide with Examples

Master JSON.stringify() in JavaScript: pretty-printing, the replacer function, the space argument, toJSON(), and how it handles undefined, dates, BigInt and circular references.

·8 min read

How to Fetch JSON in JavaScript (fetch + async/await)

Fetch and parse JSON in JavaScript with the fetch API and async/await — GET and POST requests, response.json(), proper error handling with response.ok, and common mistakes.

·7 min read

How to Convert JSON to an Array in JavaScript

Turn JSON into a JavaScript array — parse a JSON array, convert a JSON object to an array with Object.keys, values and entries, extract field values, and export to CSV.

·9 min read

JSON Interview Questions — A 2026 Guide for Developers

The JSON questions that actually come up in technical interviews — data types, parsing pitfalls, and system-design tradeoffs — with code examples, not just definitions.

·10 min read

package.json Explained: Every Field You Need to Know

A complete guide to package.json — the JSON file at the heart of every Node.js project. Dependencies, scripts, exports, engines and the fields that trip people up.

·10 min read

tsconfig.json Explained: The Compiler Options That Matter

Make sense of tsconfig.json — the JSON file that configures the TypeScript compiler. strict mode, module resolution, paths, and the settings worth changing.

·9 min read

Working with JSON in Rust: A serde_json Guide

Handle JSON in Rust with serde: derive Serialize/Deserialize for typed structs or use serde_json::Value, plus renaming, optional fields, and defaults.

·9 min read

Dates in JSON: ISO 8601, Timestamps & Timezone Pitfalls

JSON has no date type. Learn the right way to represent dates and times in JSON — ISO 8601, Unix timestamps — and how to avoid the classic timezone bugs.

·7 min read

Big Numbers in JSON — Why Large IDs Silently Break in JavaScript

JSON.parse turns every number into a 64-bit float, which quietly loses precision above 2^53. Here's exactly where that bites — 64-bit database IDs, Snowflake IDs — and how every major API works around it.

·10 min read

GeoJSON Explained: The JSON Format Behind Every Map

How GeoJSON represents points, lines and polygons as plain JSON — the format behind Google Maps exports, Mapbox, Leaflet, PostGIS and every geospatial API you'll touch.

·9 min read

JSON-LD & Schema.org: Structured Data for SEO Explained

How JSON-LD embeds machine-readable structured data in a web page — the exact format behind Google's rich results, FAQ snippets, breadcrumbs and product cards.

·9 min read

JSON in Frontend State: Structuring Redux & Zustand Stores

Your app's entire state tree is JSON-serializable data. Learn the JSON-shaped patterns behind Redux, Zustand and persisted state — normalization, immutability and localStorage sync.

·9 min read

Structuring i18n Translation JSON Files the Right Way

How react-i18next, next-intl and Flutter's ARB files structure translation JSON — nesting, pluralization, interpolation and the pitfalls that break at 20+ languages.

·10 min read

JSON in Node.js: File I/O, HTTP Servers, and Streams

A complete guide to working with JSON in Node.js — reading and writing files, building HTTP APIs, streaming large files, and validating with schemas.

·8 min read

null vs undefined in JSON: Handle Missing Values Right

null vs undefined in JSON, explained simply. See why JSON.stringify drops undefined, how to safely read missing values, and the best practice for clean API responses.

·9 min read

JSON in Python: Complete Guide with Examples

Complete guide to JSON in Python: json.loads, json.dumps, reading and writing files, requests library, converting to CSV with pandas, and handling dates.

·8 min read

JSON Has No Comments — Here's What to Use Instead

JSON intentionally has no comment syntax. Learn why, and discover JSONC, JSON5, and practical workarounds developers use every day in config files, APIs, and documentation.

·9 min read

JSON in JavaScript: parse, stringify, fetch and localStorage

Complete guide to working with JSON in JavaScript: JSON.parse, JSON.stringify, fetch API, localStorage, deep cloning, and handling dates. With examples.

·8 min read

JSON vs XML vs YAML — Which Should You Use?

A practical comparison of JSON, XML, and YAML data formats. When to use each format and how to convert between them.

·8 min read

What is JSON? A Complete Beginner's Guide

Learn what JSON is, how it works, and why it is the most popular data format for APIs and web applications in 2025.