Guides
Format comparisons, size references and step-by-step how-tos — each one paired with a free, browser-based tool.
PNG vs WebP: which should you use?
PNG vs WebP compared: file size, transparency, quality and browser support. Learn when to use each and convert between them free in your browser.
ComparisonJPG vs PNG: when to use each
JPG vs PNG explained: photos vs graphics, transparency, file size and quality. Learn which to pick and convert between them free in your browser.
ComparisonWebP vs AVIF: the next-gen image formats
WebP vs AVIF compared: compression, quality, encoding speed and browser support. Learn which to use for the web and convert free in your browser.
Size referenceApp Store screenshot sizes (2026)
The complete 2026 App Store screenshot size reference for iPhone, iPad, Mac, Apple Watch, Apple TV and Vision Pro — with the exact pixel dimensions and a free resizer.
Size referenceSocial media image sizes (2026)
Up-to-date image dimensions for Instagram, X, Facebook, LinkedIn, YouTube and Pinterest — posts, stories, thumbnails and covers — plus a free resizer.
How-toHow to resize an image for Instagram
Resize any image to Instagram's post, portrait and story sizes without losing quality — free, in your browser, no upload. Step-by-step guide.
How-toHow to compress images for the web
Shrink image file sizes for faster pages without visible quality loss. A practical guide to format choice, quality settings and batch compression — free and private.
How-toHow to convert HEIC to JPG
Convert iPhone HEIC photos to JPG so they open anywhere — free, private and in your browser. Step-by-step, with no software to install.
How-toHow to merge PDF files
Combine multiple PDFs into one document in your browser — reorder pages, no size limits, nothing uploaded. Step-by-step guide.
How-toHow to reduce PDF file size
Shrink a PDF to get it under an email or upload limit — without watermarks or uploads. A practical guide to compressing PDFs privately.
How-toHow to convert PDF to JPG
Turn PDF pages into JPG or PNG images in your browser — pick the resolution, no watermarks, nothing uploaded. Step-by-step guide.
How-toHow to crop an image
Crop a photo to any region or a fixed aspect ratio in your browser — free, private, no install. Step-by-step guide with the common ratios.
How-toHow to add a watermark to photos
Add a text or image watermark to your photos with adjustable position and opacity — free, private, in your browser. Batch-watermark a whole set at once.
How-toHow to remove EXIF metadata from photos
Strip EXIF, GPS and camera metadata from your photos before sharing — free, in your browser, nothing uploaded. Protect your privacy in a few clicks.
How-toHow to make a QR code
Create a custom QR code for a URL, text or Wi-Fi with your own colors, then download it as PNG or SVG — free, no sign-up, made in your browser.
How-toHow to generate app icons for iOS
Turn a single 1024×1024 image into every required Apple app icon size and a ready-to-drop Xcode asset set — free, in your browser, no upload.
How-toHow to resize an image without losing quality
Resize photos to exact dimensions while keeping them sharp, using high-quality resampling — free, in your browser, no upload. Practical tips inside.
How-toHow to convert SVG to PNG
Rasterize an SVG to a crisp PNG or JPG at any resolution in your browser — free, no upload. Great for tools that don't accept vectors.
ComparisonHEIC vs JPG: what's the difference?
HEIC vs JPG compared: file size, quality and compatibility. Learn why iPhones use HEIC, when to convert to JPG, and how to convert free in your browser.
ComparisonSVG vs PNG: which should you use?
SVG vs PNG compared: scaling, file size, and best use cases for logos, icons and photos. Learn when to pick each and convert SVG to PNG free.
Size referenceFavicon sizes: the complete guide
The complete favicon size reference — 16, 32, 48, 180, 192 and 512px — with what each is for, plus a free generator that makes them all from one image.
How-toHow to convert PNG to JPG
Convert PNG images to JPG in your browser — set a background for transparent areas and control quality. Free, private, no install. Step-by-step.
How-toHow to rotate a PDF
Permanently rotate PDF pages that scanned in sideways or upside-down — free, in your browser, nothing uploaded. Step-by-step guide.
How-toHow to format JSON
Beautify and indent messy JSON, validate it, and copy the result — free, in your browser, nothing uploaded. Step-by-step for readable JSON.
How-toHow to decode a JWT
Decode a JWT to inspect its header and payload claims, check expiry, and debug auth — free, in your browser. Your token never leaves the page.
How-toHow to generate a UUID
Generate random v4 or time-ordered v7 UUIDs one at a time or in bulk, and copy them instantly — free, in your browser. Learn which version to use.
How-toHow to create a strong password
Generate strong, random passwords with adjustable length and character sets, made with the Web Crypto API — free and never sent anywhere.
How-toHow to convert CSV to JSON
Convert a CSV export to a JSON array of objects — or JSON back to CSV — in your browser, with proper quoting and headers. Free, no upload.
How-toHow to convert a Unix timestamp
Convert a Unix/epoch timestamp to a human-readable date and back, across time zones, with millisecond support — free, in your browser.
How-toHow to check color contrast for accessibility
Check the contrast ratio between text and background against WCAG AA and AAA — free, in your browser, with a live preview. Make text accessible.
How-toHow to split a PDF
Split a PDF into single pages or extract a page range in your browser — free, private, no watermarks. Step-by-step guide.
How-toHow to convert images to a PDF
Combine JPG, PNG or WebP images into a single PDF in the order you choose — free, in your browser, nothing uploaded. Step-by-step guide.
How-toHow to convert JPG to WebP
Convert JPG photos to WebP for 25–35% smaller files and faster pages — free, in your browser, no install. Step-by-step guide.
How-toHow to convert WebP to PNG
Convert WebP images to lossless PNG with transparency preserved — free, in your browser, for tools that don't accept WebP. Step-by-step.
How-toHow to pixelate or censor part of an image
Pixelate an image to censor faces, plates or sensitive text — free, in your browser, nothing uploaded. Step-by-step, with a redaction caveat.
How-toHow to extract a color palette from an image
Pull a color palette with HEX values from any image — free, in your browser. Great for design systems and moodboards. Step-by-step.
How-toHow to generate a CSS gradient
Build linear and radial CSS gradients visually with multiple color stops and copy the ready-to-use code — free, in your browser. Step-by-step.
How-toHow to Base64 encode text or a file
Encode text or files to Base64, including data URLs, and decode them back — free, in your browser, nothing uploaded. Step-by-step guide.
How-toHow to URL-encode text
Percent-encode text and query parameters so they're safe in links and APIs — and decode them back — free, in your browser. Step-by-step.
How-toHow to test a regular expression
Test JavaScript regular expressions against your text with live match highlighting, capture groups and flags — free, in your browser. Step-by-step.
How-toHow to minify JSON
Strip whitespace from JSON to minify it for transport or storage, then copy the result — free, in your browser, nothing uploaded. Step-by-step.
How-toHow to turn text into a URL slug
Convert any title into a clean, URL-safe slug — lowercase, accent-stripped and hyphenated — free, in your browser. Step-by-step for pretty links.
ComparisonJPG vs JPEG: is there any difference?
JPG and JPEG are the exact same image format — the three-letter extension is a leftover from old Windows. Here's the full story, plus how to convert or compress either one free.
ComparisonYAML vs JSON: which should you use?
YAML vs JSON compared: syntax, comments, readability, parsing speed and safety. When each format wins, plus a free browser tool to convert YAML to JSON.
ComparisonAVIF vs JPG: which should you use?
AVIF vs JPG compared: AVIF is ~50% smaller at the same quality with transparency and HDR, JPG is universally compatible. When to use each, plus a free converter.
Size referenceYouTube thumbnail size: the exact specs
The correct YouTube thumbnail size is 1280×720 pixels (16:9), minimum 640px wide, under 2MB, as JPG or PNG. Full spec plus a free resizer that runs in your browser.
Size referenceOG image size: Open Graph dimensions that work everywhere
The standard Open Graph (og:image) size is 1200×630 pixels (1.91:1). Exact specs for Facebook, X/Twitter, LinkedIn and Discord, plus a free browser resizer.
Size referenceA4 size in pixels at every DPI
A4 paper (210×297mm) in pixels: 794×1123 at 96 DPI, 2480×3508 at 300 DPI. Full conversion table for every common DPI, plus free tools to resize images or make PDFs.
Size referenceiPhone screen sizes and resolutions (2026)
Complete iPhone screen size and resolution table for 2026: iPhone 17, 17 Pro, 17 Pro Max, Air, 16 series and SE — plus the App Store screenshot sizes each requires.
How-toHow to convert AVIF to JPG
Convert AVIF images to JPG free in your browser: drag in the file, pick quality, download. No upload, no signup. Fixes AVIF files that won't open in email or older apps.
How-toHow to mirror an image (flip horizontally or vertically)
Mirror any image free in your browser: flip horizontally to fix reversed selfies and text, or vertically for reflections. No upload, no watermark, no signup.
How-toHow to resize multiple images at once
Resize dozens of images to the same dimensions in one go, free in your browser: drop them in, set a target size, download all as a ZIP. No upload, no signup, no watermarks.
How-toHow to reduce PNG file size
Shrink PNG files up to 70–80% without visible quality loss: palette quantization, metadata stripping and smart resizing — free in your browser, no upload.
Size referenceCron expression syntax explained
Cron syntax decoded: what each of the 5 fields means, special characters (* / , -), common examples like '0 9 * * 1-5', and a free tool that explains any expression in plain English.
Size referenceMarkdown cheat sheet: every syntax you need
Complete Markdown cheat sheet: headings, bold, italic, links, images, code blocks, tables, lists and task lists — with a free live preview editor in your browser.
How-toHow to blur part of an image
Blur faces, license plates, names or any region of an image free in your browser: select the area, set blur strength, download. No upload — private by design.
How-toHow to make a barcode
Generate barcodes free in your browser: Code 128 for text, EAN-13/UPC for retail products. Pick a format, type your data, download as PNG or SVG. No signup.
How-toHow to convert HEX to RGB (and back)
Convert HEX color codes to RGB instantly, and understand the math: each HEX pair is one RGB channel in base 16. Free converter with HSL support, in your browser.
How-toHow to convert JSON to TypeScript interfaces
Paste JSON, get TypeScript interfaces instantly — nested objects, arrays and optional fields handled. Free in your browser; API responses never leave your device.
Size referenceiPad screen sizes and resolutions (2026)
Every current iPad's display size and resolution: iPad Pro 13" and 11" (M4), Air, mini and base iPad — plus the App Store screenshot sizes iPad apps require.
Size referenceInstagram profile picture size: the right dimensions
Instagram profile pictures are stored at 320×320 pixels and displayed as a circle. Ideal upload size, circle-crop safe zone, and a free browser resizer.
Size referenceX (Twitter) header size: exact dimensions
The X (Twitter) header size is 1500×500 pixels (3:1). Safe-zone tips so your banner isn't hidden by the profile photo, plus a free browser resizer.
How-toHow to generate a SHA-256 hash
Generate SHA-256, SHA-1 or MD5 hashes from any text free in your browser — nothing is uploaded. What hashes are for, and which algorithm to pick.
How-toHow to compare two text files and see the differences
Compare two texts or files side by side and see every added, removed and changed line highlighted — free in your browser, nothing uploaded.
How-toGlassmorphism in CSS: the frosted-glass effect
Create the frosted-glass (glassmorphism) effect in CSS: backdrop-filter blur, translucent background and a subtle border. Copy-paste code plus a free visual generator.
ComparisonUUID v4 vs v7: which should you use?
UUID v4 is fully random; UUID v7 embeds a timestamp so IDs sort by creation time — much better for database indexes. Comparison and a free generator for both.
How-toCSS box-shadow: syntax and realistic examples
Master CSS box-shadow: what each value means, why layered shadows look realistic, and copy-paste examples from subtle cards to floating modals. Free visual generator.
Size referenceWhat is lorem ipsum and where does it come from?
Lorem ipsum is scrambled Latin from Cicero, used as placeholder text since the 1500s. What it means, why designers use it, and a free generator.
How-toHow to reduce an image's size in KB
Reduce a photo to 20KB, 50KB, 100KB or any size in KB for online forms — without guessing quality settings. Free, private and works in your browser.
ComparisonDPI vs PPI: what's the difference?
DPI vs PPI explained: what each means, why changing DPI doesn't change image quality, and how many pixels you need to print at a given size.
How-toHow to change the DPI of an image
Change an image to 300 DPI or any DPI in seconds without losing quality, check the current DPI on Windows or Mac, and know when you need to resize instead.
How-toHow to add page numbers to a PDF
Add page numbers to any PDF in your browser — choose the position and style, use 'Page X of Y', skip the cover and number for double-sided printing. Free and private.
How-toMicrophone not working? How to test and fix it
Mic not picking up sound in Zoom, Teams, Meet or Discord? Test it online, then fix browser permissions, Windows and Mac privacy settings, input levels and headset issues.
How-toWebcam not working? How to test and fix it
Camera showing a black screen or not detected in Zoom, Teams or Meet? Test your webcam online, then fix permissions, privacy settings, shutters and apps using the camera.
How-toKeyboard keys not working? How to test and fix them
Some keys not typing, or typing twice? Test every key online, then fix stuck, dead and chattering keys, wrong layouts and accessibility settings on Windows and Mac.
ComparisonDead pixel vs stuck pixel: what's the difference?
Dead pixels stay black; stuck pixels stay lit in one color. Learn how to spot each with a full-screen test, which ones can be fixed, and when to claim a replacement.
How-toHow to test and fix controller stick drift
Is your character moving on its own? Test an Xbox or PlayStation controller for stick drift online, then try the fixes that work — cleaning, firmware updates, deadzones and repairs.
How-toHow to password protect a PDF
Add a password to a PDF for free without Adobe Acrobat — AES-256 encryption in your browser, optional print and copy restrictions, and tips for sharing the password safely.
How-toHow to remove a password from a PDF
Remove the password from a PDF you can already open — bank statements, payslips, e-tickets — so it opens without typing it. Free, in your browser, no upload.
How-toHow to redact a PDF properly
Black boxes and highlighters don't remove text from a PDF. Learn how to redact a PDF permanently for free — search for sensitive details, flatten pages and strip metadata.
ComparisonAPA vs MLA: what's the difference?
APA vs MLA compared side by side: in-text citations, reference lists, author names, dates and titles, with a worked example and a free generator for both styles.
ComparisonCollege ruled vs wide ruled paper
College ruled lines are 9/32 inch apart and wide ruled 11/32 inch. Compare every ruling side by side, see who each suits, and print your own lined paper free.
How-toThe Pomodoro Technique: how to use it
Work in 25-minute focus sessions with short breaks. Here's how the Pomodoro Technique works, how to adapt the intervals, common mistakes, and a free timer to start now.
How-toHow to calculate hours worked
Calculate hours worked from start and end times, subtract breaks, convert minutes to decimal hours for payroll, and work out overtime — with examples and a free calculator.
Size referenceWhat to include on an invoice
The essential details every invoice needs — invoice number, dates, itemized charges, tax and payment terms — plus tips to get paid faster and a free invoice generator.