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Guides & Tutorials

50 guides to help you get the most out of free online tools — how-to walkthroughs, deep explanations, comparisons and problem-solving tips.

how-to

How to Encode and Decode Base64: A Complete Guide

Learn what Base64 encoding is, how it works, when to use it, and how to encode and decode Base64 in your browser —no tools or signup needed.

comparison

Base64 vs Hex Encoding: Which Should You Use?

Compare Base64 and Hex encoding across efficiency, readability, use cases, and trade-offs — and learn when to pick each for binary-to-text encoding.

explanation

Color Formats Explained: HEX, RGB, and HSL

Understand the three most common web color formats —HEX, RGB, and HSL —how each represents color, when to use which, and how to convert between them.

comparison

CSV vs TSV: Which Delimiter Format Should You Use?

Compare CSV and TSV across delimiter choice, escaping, compatibility, and use cases — and learn when to pick each for tabular data.

reference

DNS Records Explained: A, AAAA, MX, TXT, CNAME, NS

A complete reference guide to DNS record types —A, AAAA, MX, TXT, CNAME, and NS —with examples, use cases, and how to look them up.

explanation

Hashing Algorithms Explained: MD5, SHA-1, SHA-256, SHA-512

Understand cryptographic hash functions: differences between MD5, SHA-1, SHA-256, and SHA-512, and which to use for integrity checks vs password storage.

how-to

How to Compress Images Without Losing Quality

Step-by-step guide to compressing images (JPEG, PNG, WebP) to reduce file size without visible quality loss using a free browser-based tool.

how-to

How to Compress PDF Files Step by Step

Step-by-step guide to compressing PDF files to reduce file size using a free browser-based tool. Learn compression levels and what affects PDF size.

how-to

How to Convert Colors Between HEX, RGB, and HSL

Step-by-step guide to converting colors between HEX, RGB, HSL, and other formats using a free browser-based tool. Learn when to use each format.

how-to

How to Convert CSV to JSON Step by Step

Step-by-step guide to converting CSV data to JSON using a free browser-based tool. Learn header handling, nested structures, and common pitfalls.

how-to

How to Convert Markdown to HTML Step by Step

Step-by-step guide to converting Markdown text to HTML using a free browser-based tool. Learn syntax, extensions, and common use cases.

how-to

How to Convert Text to Binary and Back Step by Step

Step-by-step guide to converting text to binary (0s and 1s) and decoding binary back to text using a free browser-based tool. Learn ASCII and UTF-8.

how-to

How to Convert Unix Timestamps to Human-Readable Dates (Step-by-Step)

Step-by-step guide to converting Unix timestamps (epoch) to human-readable dates and back using a free browser-based tool. Learn seconds vs milliseconds.

how-to

How to Decode JWT Tokens and Inspect Claims Safely

Step-by-step guide to decoding JWT (JSON Web Token) tokens and inspecting their header and payload claims using a free browser-based tool. Learn security boundaries.

how-to

How to Encode and Decode Base64 Strings Step by Step

Step-by-step guide to encoding text to Base64 and decoding Base64 back to text using a free browser-based tool. No upload, no signup, fully private.

how-to

How to Encode and Decode URLs Step by Step

Step-by-step guide to URL encoding (percent-encoding) and decoding using a free browser-based tool. Learn why and when to encode URLs.

how-to

How to Extract Text from PDF Files Step by Step

Step-by-step guide to extracting text content from a PDF file using a free browser-based tool. Learn scanned vs digital PDFs.

how-to

How to Format and Validate JSON Data Step by Step

Step-by-step guide to formatting (beautifying) and validating JSON data using a free browser-based tool. Catch syntax errors, minify, and pretty-print JSON instantly.

how-to

How to Generate Hash Values Step by Step

Step-by-step guide to generating cryptographic hash values (SHA-256, SHA-1, MD5) using a free browser-based tool. Learn use cases and security tradeoffs.

how-to

How to Generate Secure Passwords Step by Step

Step-by-step guide to generating strong, random passwords using a free browser-based tool. Learn password length, character sets, and security best practices.

how-to

How to Generate UUIDs Step by Step

Step-by-step guide to generating UUIDs (Universally Unique Identifiers) using a free browser-based tool. Learn UUID v4, v1, and when to use each.

how-to

How to Merge PDF Files Step by Step

Step-by-step guide to merging (combining) multiple PDF files into one using a free browser-based tool. Learn ordering and page ranges.

how-to

How to Resize Images Step by Step

Step-by-step guide to resizing images (change width and height) using a free browser-based tool. Learn aspect ratio, upscaling, and common dimensions.

how-to

How to Split PDF Files Step by Step

Step-by-step guide to splitting a PDF file into multiple parts or extracting specific pages using a free browser-based tool.

how-to

How to Test Regular Expressions Step by Step

Step-by-step guide to testing and debugging regular expressions using a free browser-based tool. Learn flags, capture groups, and common patterns.

how-to

How to Use a Color Picker to Find Colors from Any Pixel

Step-by-step guide to using a color picker to find the exact color (HEX, RGB, HSL) of any pixel in an image or on screen using a free browser-based tool.

explanation

JSON Formatting Best Practices: Readable, Valid, and Efficient

Understand the conventions for formatting JSON: indentation, key ordering, minification, trailing commas, and when to pretty-print vs minify.

explanation

Understanding JSON: A Beginner's Guide to Formatting and Validation

Learn what JSON is, its syntax rules, common data types, and how to format and validate JSON data using free online tools.

comparison

JSON vs XML: Which Data Format Should You Use?

Compare JSON and XML across syntax, verbosity, parsing speed, ecosystem support, and use cases — and learn when to pick each.

comparison

JSON vs YAML: Which Configuration Format Should You Use?

Compare JSON and YAML across readability, features, use cases, and trade-offs — and learn when to pick each for configuration and data interchange.

how-to

How to Decode a JWT and Inspect Its Claims Safely

Learn the three-part structure of a JSON Web Token, how to decode the header and payload without verifying, and why decoding is not the same as trusting.

comparison

Markdown vs HTML: Which Should You Use for Content?

Compare Markdown and HTML across readability, expressiveness, learning curve, use cases, and rendering —and learn when to pick each (or both).

problem-solving

Password Security: How to Generate, Store, and Audit Strong Passwords

Solve the most common password security problems: generating strong passwords, hashing them correctly, avoiding reuse, and auditing existing credentials.

comparison

PDF Compressor vs Image Compressor: Which Do You Need?

Compare PDF and Image compression across targets, techniques, quality trade-offs, and use cases — and learn which tool to use for your file size problem.

reference

Regular Expressions Cheat Sheet: Syntax, Flags, and Common Patterns

Complete regex reference: metacharacters, character classes, quantifiers, anchors, groups, flags, and ready-to-use patterns for emails, URLs, and dates.

how-to

How to Convert Unix Timestamps to Human-Readable Dates

Learn what a Unix timestamp is, how to convert it to a human-readable date and back, and how to handle time zones correctly when working with epoch time.

reference

Unit Conversion Reference: Length, Mass, Temperature, and Area

A complete reference of conversion factors for length, mass/weight, temperature, and area, with exact formulas and worked examples for each.

how-to

How to Encode and Decode URLs: A Complete Guide

Learn what URL encoding (percent-encoding) is, why it is required, and how to encode and decode URLs in your browser —no signup, fully private.

comparison

UUID v1 vs v4 vs v5: Which Version Should You Use?

Compare UUID versions 1, 4, and 5: how each is generated, their trade-offs in uniqueness, ordering, and determinism, and which to pick for your use case.

explanation

What Is Base64 Encoding? A Complete Explanation

A clear explanation of what Base64 encoding is, how it works, its character set, and why it is not encryption.

explanation

What Is CSV? A Complete Explanation of Comma-Separated Values

A clear explanation of what CSV (Comma-Separated Values) is, its syntax rules, common variations, and when to use CSV vs JSON.

explanation

What Is Hashing? A Complete Explanation of Hash Functions

A clear explanation of what hashing is, properties of cryptographic hash functions, common algorithms (SHA-256, MD5), and use cases.

explanation

What Is JSON? A Complete Explanation of JavaScript Object Notation

A clear explanation of what JSON (JavaScript Object Notation) is, its syntax, data types, history, and why it replaced XML as the web's data format.

explanation

What Is a JWT? A Complete Explanation of JSON Web Tokens

A clear explanation of what a JWT (JSON Web Token) is, its three-part structure, how it is used for authentication, and security considerations.

explanation

What Is Markdown? A Complete Explanation of the Lightweight Markup Language

A clear explanation of what Markdown is, its syntax, why it is popular for documentation, and how it converts to HTML.

explanation

What Is a Regular Expression? A Complete Explanation

A clear explanation of what a regular expression (regex) is, its syntax, common use cases, and why regex is powerful but hard to read.

explanation

What Is a Unix Timestamp? A Complete Explanation of Epoch Time

A clear explanation of what a Unix timestamp is, the Unix epoch, seconds vs milliseconds, and the Year 2038 problem.

explanation

What Is URL Encoding? A Complete Explanation of Percent-Encoding

A clear explanation of what URL encoding (percent-encoding) is, which characters need encoding, and how it works.

explanation

What Is a UUID? A Complete Explanation of Universally Unique Identifiers

A clear explanation of what a UUID is, its versions (v1, v4, v5), structure, collision probability, and when to use UUIDs.

how-to

How to Count Words, Characters, and Reading Time Accurately

Learn how word and character counts are defined across languages, how to estimate reading time, and how to use a counter to hit limits for essays, tweets, and meta descriptions.