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A REST API is the most common way for web services to communicate. When your app fetches user data, submits a form, or loads a product catalog, it's almost certainly talking to a R…
Read Guide →HTTP methods tell a server what action to take on a resource. Every REST API request uses one of a h…
Read Guide →Testing API endpoints before writing code saves significant debugging time. Sending a raw HTTP reque…
Read Guide →Popular Guides
JSON Viewer & Formatter
JWT Toolkit
Base64 Text Encoder & Decoder
Regex Tester
UUID Generator
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Testing an API endpoint usually means firing up Postman, writing a curl command, or switching to a terminal. DevDeck's A…
Read Guide →Raw JSON from an API or log file is often a single compressed line with no whitespace. Formatting it — adding indentatio…
Read Guide →Invalid JSON is one of the most common causes of broken API integrations and configuration errors. A single missing comm…
Read Guide →JSON (JavaScript Object Notation) has a small, strict syntax. Six data types, two container structures, and a handful of…
Read Guide →Most JSON errors are caused by a small set of syntax mistakes. The parser message tells you where the error is, but not …
Read Guide →JSON5 is a superset of JSON that adds several features developers often wish standard JSON had: comments, trailing comma…
Read Guide →Migrating from custom CSS to Tailwind means replacing property-value pairs with utility classes. Most CSS properties map…
Read Guide →The fastest way to learn CSS-to-Tailwind conversion is through real examples. This guide shows complete conversions for …
Read Guide →Beyond basic property mapping, Tailwind has patterns for pseudo-classes, responsive breakpoints, dark mode, transitions,…
Read Guide →Tailwind's responsive system replaces CSS media queries with breakpoint prefixes on utility classes. It's mobile-first —…
Read Guide →Migrating a project from plain CSS to Tailwind CSS or converting a CSS snippet for use in a React component? DevDeck's C…
Read Guide →Raw JSON from APIs is often a single unreadable line. JSON Viewer formats it instantly, validates the syntax, and lets y…
Read Guide →JWT Toolkit is a complete JWT workbench. Decode any token to inspect its claims, and generate cryptographically signed J…
Read Guide →Base64 encoding turns binary data into a string of printable ASCII characters. It's used everywhere in web development —…
Read Guide →A Base64-encoded image is a text string that represents image binary data. Decoding it reveals the original image. This …
Read Guide →A data URL is a URI scheme that lets you embed file content directly inside an HTML document or CSS stylesheet. Instead …
Read Guide →Should you embed an image as Base64 or serve it as a regular file? The answer depends on image size, how many pages use …
Read Guide →Base64 text encoding converts any string into a safe ASCII representation. It's widely used in HTTP Basic Auth headers, …
Read Guide →Base64 image conversion lets you embed images directly into HTML, CSS, or JavaScript as text strings. No separate file r…
Read Guide →Cryptographic hashes are one-way fingerprints of data. Use them to verify file integrity, store passwords safely, genera…
Read Guide →Weak passwords are the leading cause of account breaches. Password Generator creates cryptographically random passwords …
Read Guide →UUIDs are the standard way to generate unique identifiers without a central authority. DevDeck's UUID Generator has two …
Read Guide →Regular expressions are powerful but notoriously hard to write and debug. DevDeck's Regex Tester has two modes: a live T…
Read Guide →Unix timestamps are the number of seconds (or milliseconds) since January 1, 1970 UTC. They appear in logs, databases, a…
Read Guide →Computers think in binary. Programmers read hex. Humans use decimal. Number Base Converter instantly translates between …
Read Guide →CSV is the universal format for spreadsheet exports and database dumps, but modern APIs and apps expect JSON. Convert CS…
Read Guide →YAML is the language of configuration files — Kubernetes, Docker Compose, GitHub Actions, Ansible all use it. But APIs s…
Read Guide →Spotting differences between two versions of text — code, JSON, config files, or documents — is tedious without the righ…
Read Guide →Different coding conventions demand different text cases: API fields use camelCase, Python uses snake_case, CSS uses keb…
Read Guide →Whether you're writing a tweet (280 chars), a cover letter (400 words), or a blog post (800 words), knowing your word an…
Read Guide →Lorem ipsum is the industry-standard placeholder text used in design mockups, wireframes, and prototypes. Generate exact…
Read Guide →QR codes bridge the physical and digital world. Generate a QR code for any URL, contact, WiFi credentials, or text — ins…
Read Guide →Long URLs are awkward in messages, tweets, and printed materials. URL Shortener converts any URL into a short, shareable…
Read Guide →A URL contains protocol, domain, path, query parameters, and fragments — each with its own rules. URL Validator breaks a…
Read Guide →Resizing images for different contexts — web thumbnails, social media posts, email banners — usually requires Photoshop …
Read Guide →Color codes come in multiple formats depending on the context — CSS uses HEX or RGB, design tools use HSL, and APIs may …
Read Guide →Aspect ratio describes the proportional relationship between width and height. Whether you're designing for video, web l…
Read Guide →Smart Formatter is a universal data formatter that detects what you've pasted and formats it correctly — without you hav…
Read Guide →JSX looks like HTML, but it's actually a JavaScript syntax extension. The two share the same tag names and most attribut…
Read Guide →Converting HTML to JSX looks straightforward until you hit the subtle differences — class becomes className, onclick bec…
Read Guide →Pasting HTML into a React component almost always produces errors. The differences between HTML and JSX are small but st…
Read Guide →JSX is the syntax extension that lets you write markup inside JavaScript. It looks like HTML but compiles to JavaScript …
Read Guide →Copying HTML into a React component always requires manual cleanup — class becomes className, for becomes htmlFor, oncli…
Read Guide →Encoder / Decoder is a multi-format encoding tool that covers every encoding scheme developers regularly encounter — Bas…
Read Guide →Command Playground is DevDeck's smart routing layer. Paste any data — a JSON blob, a JWT token, a URL, a UUID, a Base64 …
Read Guide →Cron expressions power scheduled jobs on Linux servers, cloud functions, CI pipelines, and almost every backend system. …
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