67 tools · 17 guides · 0 uploads · 0 sign-ups
Free online tools that run in your browser
Format JSON, test regular expressions, minify CSS, score email subject lines and more. Every tool on Utilshut runs on your device — what you paste is processed in your browser, not intentionally sent to an application server by Utilshut.
Browse by category
All 67 tools →JSON Tools
Format, validate, diff and convert JSON.
13 tools →CSV & Data Tools
Convert, clean and reshape CSV data.
6 tools →Encoders & Converters
Base64, URL, entities, number bases and timestamps.
6 tools →CSS & Color Tools
Gradients, palettes, color conversion and minifying.
4 tools →Image Tools
Resize, compress, convert and clean up images.
12 tools →Audio Tools
Trim, convert, boost and record audio.
7 tools →PDF Tools
Protect, unlock, fill and sign PDFs.
4 tools →Text & Writing Tools
Count words, convert case and translate Markdown.
6 tools →Email Tools
Subject lines, spam checks and signatures.
3 tools →Developer Tools
Regex, UUIDs, hashes, JWTs and diffs.
6 tools →Popular tools
See everything →JSON Formatter
Beautify and pretty-print JSON with 2-space, 4-space, or tab indentation.
Open tool →Image Compressor
Shrink JPEG and WebP file sizes with a quality slider and live before/after comparison.
Open tool →Sign PDF
Draw or upload a signature and place it on any page — signed on-device, not intentionally uploaded to an application server by Utilshut.
Open tool →Word Counter
Count words, characters, sentences, paragraphs and reading time live.
Open tool →Image Resizer
Resize images to exact pixels or a percentage — right in your browser, processed in your browser.
Open tool →CSV to JSON Converter
Turn CSV data into a JSON array of objects, with automatic type detection.
Open tool →Protect PDF with Password
Encrypt a PDF with AES-256 right in your browser — the file is designed to be processed in your browser.
Open tool →Regex Tester
Test JavaScript regular expressions against sample text with live matches.
Open tool →Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to text. Full UTF-8 support.
Open tool →JWT Decoder
Decode a JSON Web Token's header and payload and check its expiry — locally.
Open tool →UUID Generator
Generate random UUID v4 identifiers — one or hundreds at a time, cryptographically random.
Open tool →Image Converter
Convert images between PNG, JPEG and WebP with browser canvas APIs.
Open tool →Guides
All 17 guides →What Is JSON? A Plain-English Guide
What JSON is, what it looks like, and why every API speaks it.
Read guide →Regex Cheat Sheet
Every regex token that matters: classes, quantifiers, groups, anchors and lookarounds, with examples.
Read guide →How to Password Protect a PDF
Free ways to encrypt a PDF on any device without Acrobat, and how strong each one is.
Read guide →PNG vs JPEG vs WebP
Which image format to use when: quality, transparency, file size and browser support compared.
Read guide →How to Compress Images for the Web
Get image files small without visible quality loss: formats, quality settings and workflow.
Read guide →What Is Base64 Encoding?
How Base64 turns binary into text, why it's everywhere, and why it isn't encryption.
Read guide →Why these tools are different
Most online utility sites send your data to a server to process it. Everything on Utilshut is built as a client-side web app: the formatting, encoding, testing and converting all happen in JavaScript inside your own browser tab. That makes each tool instant to use, keeps sensitive data like API responses or email drafts out of server hands, and works even on a flaky connection once the page has loaded.
The collection covers the small jobs developers, marketers and writers hit every day: cleaning up a minified JSON payload, checking whether a regex actually matches, converting a Unix timestamp from a log file, or sanity-checking an email subject line before a send. The JSON section runs deepest — everything from formatting to diffing to TypeScript generation, backed by in-depth guides — and more categories will grow the same way over time.