Guides

Practical guides for the jobs the tools do: which format to pick, how to hit a size limit, how to fix a broken file, and what the settings actually change.

Images

Image formats explained: JPG, PNG, WebP, AVIF, GIF, BMP and ICO

Which format to use for photos, logos, screenshots, web pages, print and social, and why.

Image sizes for websites, email and social media

A reference table of pixel dimensions and ratios for web pages, link previews, email and every major social platform.

How to open HEIC files on Windows

Why iPhone photos will not open on a Windows PC, and three free ways to fix it.

HEIC vs JPG: the differences that matter

Size, quality, compatibility and editing compared, and when converting is worth it.

How to compress an image to a specific size

The right order of steps to hit a KB limit and keep the photo sharp.

Photo and signature requirements for online forms

Getting a photo and signature through an application form the first time.

How to make images load faster on a website

The five changes that cut image weight on any website, in order of impact.

Using WebP images in WordPress, Shopify and Wix

What each platform does with WebP, and when to convert images yourself.

How to make a favicon

The sizes, formats and code you need for a favicon that shows everywhere.

How to preview social media posts before publishing

Catch cropping, caption and carousel problems before a post goes live.

PDF

How to reduce the size of a PDF

Diagnose why a PDF is large, then shrink it the right way for email limits, portals and storage.

How to sign a PDF without printing it

Draw or upload your signature, place it on the page, and send the PDF back in minutes.

How to fill in a PDF form

Fillable forms, flat forms that only look fillable, and locking your answers.

How to combine scanned documents into one PDF

From a pile of paper to one small, well-ordered PDF you can email.

How to remove pages from a PDF

Two ways to cut pages out of a PDF, and when to use each.

Spreadsheets and data

Why a CSV shows weird characters in Excel

The encoding mix-up behind garbled accents, and three ways to fix it.

CSV vs Excel: which format to use

What each format can hold, what gets lost in conversion, and when to choose which.

How to remove duplicates in Excel and Google Sheets

The built-in tools in Excel and Sheets, and a faster way for plain lists.

How to open a CSV file that is too large for Excel

What to do when Excel says a CSV did not load completely.

How to clean an email list before a campaign

A short routine that cuts bounces and protects your sender reputation.

Video and audio

How to compress a video for WhatsApp, email and the web

The size limits on each platform, what resolution and bitrate do, and settings that get a clip under the limit.

How to extract audio from a video as MP3

Pull the sound out of a video file, and choose the right quality for it.

How to make a GIF from a video

Clip length, width and frame rate: the three settings that decide GIF size.

Files and privacy

Why processing files in your browser is more private than uploading them

What happens to your file on a normal converter site, how on-device processing works, and how to verify it.

ZIP, GZIP, TAR, 7z and RAR explained

What each archive format does, where it opens without extra software, and which one to use for a given job.

Email attachment size limits, and how to get under them

The limits for the main email services, and the quickest way to shrink each kind of file.

How to batch rename photos and files

Turn IMG_4821.jpg into names that sort, search and make sense.

Put the guides to work

Every guide goes with tools that do the job it describes, entirely in your browser.

Images: compress images, convert PNG to WebP, resize images and enhance a photo.
PDF: compress a PDF, merge PDFs, edit a PDF and turn images into a PDF.
Video: compress a video, extract audio as MP3 and make a GIF.
Archives: create a ZIP and open a ZIP.