CSS Grid Cheatsheet: Every Property With Visual Examples
The complete CSS Grid reference — every container and item property explained with practical examples, common layout patterns, and a free visual Grid generator.
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Free Tools
All articles tagged with “Free Tools”.
How to Convert JSON to CSV (and Back) Without Writing Code
Need to convert JSON to CSV for a spreadsheet, or CSV back to JSON for an API? Learn when each format makes sense, where conversions go wrong, and convert instantly free in your browser.
Read ArticleHTTP Headers Explained: What Every Developer Should Know
HTTP headers control caching, security, content type, authentication, and more. Learn what every important request and response header does — and how to read them like a pro.
Read ArticleWhat Is CORS and How Do You Fix It? A Plain-English Guide
CORS errors block your fetch requests before they reach your code. Learn why the browser enforces the Same-Origin Policy, how preflight requests work, and how to fix every common CORS error on Apache, nginx, Node, and PHP.
Read ArticleHow to Read and Write Cron Job Expressions (With Examples)
Cron syntax looks cryptic until you understand its five fields. Learn how to read and write cron expressions, use every special character, avoid common scheduling mistakes, and build any schedule with a free visual tool.
Read ArticleWord Counter and Text Tools Every Developer Should Know About
Word counters, case converters, slug generators, and lorem ipsum tools solve small but frequent developer tasks instantly. Learn what each tool does and when to reach for it.
Read ArticleFree Developer Tools That Replace Paid Software (2026 Roundup)
Paid developer tools are often unnecessary. Here are the best free, browser-based alternatives covering formatting, encoding, security, CSS, design, and API testing — all on DevToolShack.
Read ArticleHow to Audit and Improve Your Website's Page Speed (Free Tools)
Slow pages lose visitors and rank lower in Google. Learn how to audit your page speed, find what's slowing you down, and fix the biggest issues using free browser-based tools.
Read ArticleThe .htaccess Cheatsheet: Redirects, Security Headers, and More
.htaccess is the Apache config file that controls redirects, security headers, custom error pages, and access rules. Learn the most useful directives and generate them free.
Read ArticleHow to Check Your IP Address and What the Info Means
IP lookup tools reveal geolocation, ISP, ASN, and more. Learn what your IP address tells the world, how to look up any IP instantly, and why developers use this daily.
Read ArticleCSS Specificity Explained: Why Your Styles Keep Getting Overridden
CSS specificity is the algorithm that determines which style wins when multiple rules target the same element. Understand it once and CSS becomes far less frustrating.
Read ArticleYAML vs JSON: When to Use Each in Your Projects
YAML and JSON store the same data but feel completely different to write and read. Learn the key differences, when each shines, common YAML gotchas, and convert instantly free.
Read ArticleHow to Generate Favicons for Every Device (And Why It Matters)
A favicon isn't just one file anymore — modern sites need dozens of sizes for browsers, mobile home screens, and PWAs. Learn what you need and generate them all instantly free.
Read ArticleDiff Tools for Developers: Finding What Changed Between Two Files
Diff tools reveal exactly what changed between two versions of text, code, or data. Learn how diff works, the formats it produces, and compare any text instantly free.
Read ArticleHow to Create a CSS Gradient: Linear, Radial, and Conic Explained
CSS gradients are more powerful than most developers use them. Learn linear, radial, and conic gradients — every syntax option, layering tricks, and a free visual generator.
Read ArticleSVG Optimization: Why Your SVGs Are Too Big and How to Fix Them
SVG files exported from design tools are bloated with unnecessary metadata. Learn what makes SVGs large, what's safe to remove, and optimize them instantly free in your browser.
Read ArticleHow to Look Up DNS Records Online (And What They Mean)
DNS records control where your domain points and how email is routed. Learn what A, CNAME, MX, TXT, and NS records do — and look up any domain's records instantly free.
Read ArticleCSS px vs rem: Why You Should Stop Using Pixels for Font Sizes
Pixels ignore the user's browser font size preference — rem doesn't. Learn the difference between px, rem, and em in CSS, when to use each, and convert values instantly free.
Read ArticleCron Expressions Explained: Scheduling Jobs Without the Headache
Cron expressions look cryptic but follow a simple pattern. Learn every field, common schedules, the gotchas that catch people out, and build expressions with a free visual tool.
Read ArticleHow to Generate and Use HMAC Signatures for API Security
HMAC signatures let APIs verify that requests are authentic and unmodified. Learn how HMAC works, how to sign and verify requests, and generate signatures instantly free.
Read ArticleJSON vs CSV vs XML: Which Data Format Should You Use?
JSON, CSV, and XML all store data — but they're built for different jobs. Learn when to use each, how to convert between them, and which format your project actually needs.
Read ArticleThe Developer's Guide to Color Contrast and Accessibility
Poor color contrast makes your site unusable for millions of people — and fails legal compliance. Learn WCAG contrast ratios, how to test them, and fix failures fast.
Read ArticleHow to Build a Robots.txt File That Won't Accidentally Block Google
A misconfigured robots.txt can deindex your entire site overnight. Learn the syntax, common mistakes, what to block and what not to, and generate one correctly free.
Read ArticleCSS Border Radius: The Complete Visual Guide
CSS border-radius goes deeper than rounded corners. Learn every syntax variant, how to create pills, circles, and asymmetric blob shapes, plus a free visual generator.
Read ArticleBCrypt Hashing Explained: Why It's the Gold Standard for Passwords
BCrypt is deliberately slow — and that's the point. Learn why fast hashing algorithms are wrong for passwords, how BCrypt works, and how to use it correctly in your apps.
Read ArticleMarkdown to HTML: When and Why to Convert (With Free Tool)
Markdown is great for writing — HTML is what browsers render. Learn when to convert between the two, the syntax that maps to what, and convert instantly free in your browser.
Read ArticleHow to Use cURL: A Beginner's Guide With Command Generator
cURL is the essential tool for testing APIs, debugging HTTP, and automating requests from the terminal. Learn the most useful flags and generate commands free in your browser.
Read ArticleColor Theory for Developers: HEX, RGB, and HSL Explained
HEX, RGB, HSL — three ways to describe the same color. Learn what each format means, when to use each in CSS, and how to convert between them instantly free.
Read ArticleHow to Minify CSS and JS Without a Build Tool
Minifying CSS and JavaScript reduces file sizes and speeds up your site — no Webpack or build pipeline required. Learn what minification does and how to do it instantly free.
Read ArticleUnix Timestamps Explained: What They Are and How to Convert Them
Unix timestamps are the universal language of time in programming — but converting them by hand is a pain. Learn what they are, common pitfalls, and convert them instantly free.
Read ArticleThe Complete Guide to Open Graph Tags for Social Sharing
Open Graph tags control how your pages look when shared on Facebook, LinkedIn, Slack, and more. Learn every tag, the right image sizes, and generate them instantly free.
Read ArticleHow to Read and Debug HTTP Status Codes
HTTP status codes tell you exactly what went wrong — if you know how to read them. A practical guide to every code class, the most common codes, and how to debug each.
Read ArticleCSS Grid vs Flexbox: When to Use Each (With Visual Examples)
Grid and Flexbox solve different layout problems — and knowing which to reach for saves hours of fighting CSS. Here's how to choose, with practical examples of each.
Read ArticleQR Codes for Developers: When, Why, and How to Generate Them
QR codes aren't just for menus — developers use them for app links, Wi-Fi sharing, 2FA setup, deep links, and local dev testing. Learn how they work and generate them free.
Read ArticleHow to Check SSL Certificates Online (And What to Look For)
SSL certificate errors kill user trust and break HTTPS. Learn how to check any certificate's validity, expiry, chain, and common failure modes — free, in your browser.
Read Article10 Text Tools Every Developer Should Bookmark
From word counters to diff checkers, these free browser-based text tools solve the small problems that slow developers down every day. All free, no sign-up needed.
Read ArticleJWT Decoded: Understanding JSON Web Tokens Without the Jargon
JWTs are everywhere in modern auth — but most developers use them without truly understanding them. Learn what's inside a token, how signing works, and common pitfalls.
Read ArticleCSS Flexbox Cheatsheet: Every Property Explained With Examples
The complete CSS Flexbox reference — every container and item property explained with practical examples, common layout patterns, and a free visual Flexbox tool.
Read ArticleHow to Use the Meta Tag Generator to Improve Your SEO Instantly
Meta tags control how your pages appear in search results and social shares. Learn which tags matter, what to write in them, and generate a perfect set in seconds.
Read ArticleMD5 vs SHA-256: Which Hash Should You Use and Why
MD5 and SHA-256 both produce hashes — but they're not interchangeable. Learn what each is good for, why MD5 is broken for security, and when to use which algorithm.
Read ArticleURL Encoding Explained: Why Your URLs Break and How to Fix Them
URLs break when special characters aren't encoded correctly. Learn what percent-encoding is, which characters need it, and how to fix broken URLs instantly.
Read ArticleCSS Box Shadow: A Complete Guide With a Visual Generator
Master CSS box-shadow — every parameter explained, layered shadows, inset shadows, common design patterns, and a free visual generator to build them without guessing.
Read ArticleHow to Generate Strong Passwords (And What Makes One Actually Secure)
What actually makes a password strong? Length, randomness, entropy — explained plainly. Plus how to generate and check secure passwords instantly in your browser.
Read ArticleThe Developer's Guide to UUID vs Nano ID: Which Should You Use?
UUID and Nano ID both generate unique identifiers — but they make different trade-offs. Here's how to choose the right one for your database keys, URLs, and tokens.
Read ArticleBase64 Encoding Explained: What It Is and When to Use It
Base64 isn't encryption — it's encoding. Learn what it actually does, when to use it, when not to, and how to encode and decode instantly in your browser.
Read ArticleRegex for Beginners: Writing Your First Patterns (With a Live Tester)
Regular expressions look intimidating but they're built from just a handful of simple concepts. Learn anchors, character classes, quantifiers, and real-world patterns with a live tester.
Read ArticleHow to Format and Validate JSON Online Without Installing Anything
Raw JSON is nearly impossible to read. Learn how to format, validate, and debug JSON instantly in your browser — no tools to install, no accounts to create.
Read ArticleTry the tools yourself — free.
Format, encode, generate, and convert — everything runs client-side. No account needed.