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Developers & DevOps

Developer tool guides

Tutorials for JSON formatting, JWT decoding, HTML beautification, text diff, URL encoding, binary conversion, and DNS lookup — free in the browser.

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Featured guides

Binary Converter Guide — Binary ↔ Decimal

Convert between binary and decimal for networking homework, subnet masks, and embedded register docs.

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Developer Tools Hub — JSON, JWT, HTML & DNS Utilities

Free browser utilities for JSON formatting, JWT decoding, HTML beautification, text diff, URL encoding, and DNS lookup.

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DNS Lookup Guide — A, MX, TXT Records

Query DNS for email migration, domain verification, and CDN cutover troubleshooting.

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HTML Formatter Guide — Beautify Markup for Review

Indent HTML templates and CMS fragments for readable diffs before HTML-to-PDF export.

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Image to Base64 Guide — Data URLs for HTML & APIs

Convert small images to Base64 data URIs for HTML email and JSON payloads. Size inflation warnings.

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JSON Formatter Guide — Pretty-Print & Validate JSON

Format API responses and config files. Spot syntax errors before deploy and pair with text diff tools.

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JWT Decoder Guide — Inspect Token Claims Safely

Decode JSON Web Token header and payload. exp, iss, aud claims and why decoding is not verification.

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Text Comparer Guide — Diff Two Text Blocks Online

Side-by-side text diff for config changes, contract redlines, and JSON before/after formatting.

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URL Encoder Guide — Percent-Encoding Query Strings

Encode and decode URL parameters safely for OAuth redirects, analytics tags, and API links.

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Format & parse

Pretty-print payloads and inspect structured data.

JSON Formatter

Validate and indent JSON for API debugging.

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JWT Decoder

Read header and payload claims from tokens.

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HTML Formatter

Beautify HTML templates before review or export.

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Compare & encode

Diff text and encode URL query parameters.

Text Comparer

Side-by-side diff for configs and redlines.

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URL Encoder

Percent-encode query string values.

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URL Decoder

Decode percent-encoded URLs.

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Conversion & network

Binary math, Base64 data URIs, and DNS lookups.

Binary to Decimal

Convert bit strings to decimal.

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Decimal to Binary

Convert integers to binary.

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Img to Base64

Embed small images as data URIs.

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DNS Lookup

Query A, MX, TXT, and other records.

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Browser OCR Tool

Extract text from images in the browser.

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More developer guides

Step-by-step help for JSON formatting, JWT decode, HTML cleanup, and more.

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Further reading