Merge PDF
Merge PDFs online for free
DevDrills — Free Online Developer Tools
Format JSON, minify HTML and CSS, merge PDFs, generate UUIDs and more. Every DevDrills tool runs entirely in your browser — your files are never uploaded, and there is no signup.
Part of DevDrills.
PDF Tools
Combine, compress, convert, and edit PDF files right in your browser. No signup, no uploads to any server — your files stay on your device.
Randomizers
Make a call you cannot argue with. Every result is drawn from your browser's cryptographic random generator, not a shuffled list.
Text & Content Tools
Generate slugs, convert text case, create placeholder text, and more.
Text to Slug Converter
Turn any text into clean, URL-friendly slugs. Works great for blog posts, product pages, and web pro...
Case Converter
Support for camelCase, snake_case, kebab-case, and custom transformations.
Lorem Ipsum Generator
Get placeholder text for your designs and mockups in 48+ languages. Pick paragraphs, sentences, word...
EPUB Reader
Drop in an .epub file and start reading. Jump between chapters, resize the text, and switch to dark ...
Images Editing Tools
All essentials for image editing are available in one place.
Online Calculators
Age calculator, percentage calculator, loan EMI, calorie counter, and more.
Unit Converter Tools
Access our most popular converters quickly.
Binary Converter Tools
Binary converter tools for all your needs.
Security & Developer Tools
Create UUIDs and other unique identifiers for your apps. Free, no signup needed.
HTML Tools
Write markup with a live preview, then beautify it, minify it, validate the structure, or convert it to Markdown, JSX or plain text. Nothing is uploaded and nothing is stored on a server, so pasting client work or an unreleased page is not a decision you have to think about.
HTML Editor
Write HTML, CSS and JavaScript side by side and watch the page render as you type.
HTML Formatter
Reindents minified or messy markup so the structure of the document is readable again.
HTML Minifier
Strips comments and collapses whitespace, then tells you exactly how many bytes went.
HTML Cleaner
Paste from Word or Google Docs and get semantic markup back, minus the junk.
HTML Encoder & Decoder
Escape characters into entities or decode them back — named, decimal and hex all work.
HTML to Markdown Converter
Turns HTML into clean Markdown with tables, task lists and code fences left intact.
Markdown to HTML Converter
Renders Markdown into HTML you can paste anywhere, with a preview of the result.
HTML to JSX Converter
Rewrites markup as JSX: className, htmlFor, style objects and self-closed tags.
HTML to Text Converter
Drops every tag and keeps the words, with paragraph breaks where they belong.
HTML Validator
Finds unclosed tags, mismatched elements and deprecated markup, one line at a time.
HTML Viewer
Paste a page and see it rendered instantly in a sandboxed frame. No file needed.
CSS Tools
Edit CSS against real markup with a live preview, then format it, minify it, sort properties so diffs behave, add the prefixes older engines still want, or pull out every colour and selector a file contains. All of it runs on your own machine.
CSS Editor
Write CSS against real markup and watch every change land in the preview.
CSS Formatter
Turns a minified or inconsistent stylesheet into rules you can read and review.
CSS Minifier
Cuts comments, whitespace and slack from a stylesheet, and counts the bytes saved.
CSS Property Sorter
Alphabetises declarations inside every rule so diffs stop moving around between edits.
CSS Comment Remover
Deletes every comment and leaves the rules exactly as they were.
CSS Vendor Prefixer
Adds the -webkit- and -moz- prefixes older engines still need to apply your rules.
CSS Color Extractor
Pulls every hex, rgb and hsl value out of a stylesheet into one auditable list.
CSS Selector Extractor
Lists every selector in order, which makes it obvious what a file actually targets.
CSS Viewer
Preview a stylesheet against a sample page and judge colour, spacing and layout.
CSS Validator
Catches unbalanced braces, missing semicolons and the property names you misspelled.
JavaScript Tools
Run snippets against a real page with a console attached, then beautify, minify, strip comments, obfuscate, deobfuscate or validate. Your code never leaves the tab, which matters when the code is not yours to upload.
JavaScript Editor
Run JavaScript against a real page and read every log and error in the console.
JavaScript Formatter
Reindents minified or inconsistent code into something a reviewer can follow.
JavaScript Minifier
Strips comments and whitespace to shrink a file, and reports what you saved.
JavaScript Comment Remover
Removes line, block and JSDoc comments without touching strings that merely look like them.
JavaScript Obfuscator
Renames identifiers and hex-encodes strings so source is harder to read at a glance.
JavaScript Deobfuscator
Decodes hex and unicode escapes, then reformats, so you can see what code does.
JavaScript Runner
Run a snippet in a sandboxed frame and read the console without opening devtools.
JavaScript Validator
Points at the unbalanced bracket or unterminated string before you ship it.
JSON Tools
Beautify or minify a payload, sort keys so two files line up in a diff, flatten nesting for a translation file, repair the trailing comma that broke a parse, convert to YAML, or list every path the document contains.
JSON Toolkit
Ten JSON tools sharing one editor — format, repair, convert and inspect any payload.
JSON Formatter
Turns one dense line into indented structure you can actually read.
JSON Minifier
Squeezes every space and newline out of a payload before it goes over the wire.
JSON Key Sorter
Sorts keys alphabetically at every level so two files finally line up in a diff.
JSON Flattener
Collapses nesting into dot-notation keys, the shape translation files expect.
JSON Repair Tool
Fixes the usual suspects: trailing commas, single quotes and unquoted keys.
JSON to YAML Converter
Converts a payload into the YAML that Compose, Actions and Kubernetes expect.
JSON Escape Tool
Wraps JSON as a string literal you can drop into code or another document.
JSON Unescape Tool
Turns an escaped string literal back into JSON you can read or reformat.
JSON Path Extractor
Lists every dotted path and array index, so a payload’s shape stops being guesswork.
JSON Validator
Tells you the exact line and column where parsing broke, not just that it did.
Encoding & Encryption Tools
MD5 hash generator, Base64 encoder/decoder, and more.
Security & Privacy Tools
Create strong passwords, secure PINs, and more. Free, no signup needed.
Frequently Asked Questions
DevDrills Tools is a free platform with 60+ browser-based tools across six areas — HTML, CSS, JavaScript, JSON, PDF, and text and content utilities. Everything runs right in your browser tab. No installs, no signups, and nothing you paste is uploaded.
Yes — every single tool is 100% free. No hidden costs, no premium tiers, no credit card, no usage limits. Use them as much as you want.
Nope. Just open any tool and start using it. No account, no signup, no personal info needed.
Yes. Most tools process everything right in your browser using client-side JavaScript. Your files, text, passwords, and other inputs never leave your device. We don't collect, store, or send your data anywhere.
Sixty-two at the moment, and the count grows. The breakdown: JSON tools (10 plus the editor), HTML tools (10 plus the editor), CSS tools (9 plus the editor), JavaScript tools (7 plus the runner), PDF tools (4), and 16 standalone utilities including a UUID generator, password generator, lorem ipsum generator, slug converter, case converter, EPUB reader, QR code generator and MD5 hasher.
Yes. Both use the Web Crypto API (crypto.getRandomValues) for cryptographically secure random number generation. That means true randomness — solid enough for auth tokens, API keys, and database identifiers.
Yes. Everything works on phones, tablets, and desktops. The interface adapts to your screen size, so you get the same experience whether you're on an iPhone, Android, iPad, or desktop.
Most tools give you instant results because they run client-side in your browser — there's no server round-trip. Code formatting, text conversion, password generation, UUID creation — all done in milliseconds.
Yes. Most tools let you copy to clipboard or download as TXT, CSV, JSON, or XML. Image tools support PNG, JPG, and WebP downloads. The exact options depend on the tool.
Regularly, based on what people actually ask for. Tool requests sent through the contact form are prioritised by how often they come up. Follow us on social media or check back to see what's new.
Head to our Contact page or email us directly. Let us know which tool you were using, what you expected, and what actually happened. Screenshots help a lot — we fix reported issues fast.
Learn & Explore
Tips, guides, and insights from our blog
Security7 min read
How to Create Strong Passwords in 2026: A Simple Guide
Practical tips for creating passwords that actually keep your accounts safe. Covers password security, managers, and two-factor authentication — no fluff.
Development10 min read
What is a UUID? Complete Guide to Unique Identifiers
A straightforward look at UUIDs — what they are, how they work, and how to actually use them in your apps.
Design8 min read
What is Lorem Ipsum? History, Meaning, and Modern Uses
The 2000-year story of Lorem Ipsum — from Cicero's Latin philosophy to modern web design. Plus why designers still use it and how to generate it yourself.
SEO10 min read
URL Slugs: The Complete SEO Guide for 2026
What URL slugs are, why they matter for search rankings, and how to get them right. Covers best practices and common mistakes to watch out for.