Guides
Why a HEIC won't open, what a 50 KB limit really means, what size a passport photo has to be. Short, practical, and free of the usual filler.
Why won't my HEIC photos open on Windows?
HEIC is Apple's default photo format and Windows often can't open it. Here's why, three ways to fix it, and how to stop your iPhone making HEIC at all.
Read the guideHow to compress a photo for an online form
Forms reject photos for being too large. Here's what those KB limits mean, how to hit 50 KB or 100 KB exactly, and what to do about dimension limits.
Read the guidePassport photo sizes, and how to make one that's accepted
Passport photo sizes by country, what 35 × 45 mm means in pixels, the file size limits portals impose, and the reasons photos get rejected.
Read the guideWhy does the form keep rejecting my photo?
Upload forms reject photos for six predictable reasons — file size, dimensions, format, colour mode, file name and the photo itself. Here's which one.
Read the guideWebP vs AVIF vs JPG: which should you use?
How WebP, AVIF, JPG and PNG compare on file size, quality, transparency and support — and a simple rule for choosing between them.
Read the guideWhy is my AI-generated image so big?
AI generators hand you a lossless PNG of several megabytes. Here's why it's so large, and how to resize and convert it for the web without uploading.
Read the guideHow to tell if an online image tool uploads your photo
Most online image tools upload your photo to a server. Two tests show you what a tool really does in under a minute, plus the wording that gives it away.
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