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Image guides

Clear, practical explanations of image formats, file sizes and photo requirements — written by the Pixora team.

JPG vs PNG vs WebP vs AVIF: which image format should you use?

A clear comparison of the four most popular image formats — quality, file size, transparency and compatibility — with simple rules for choosing the right one.

Read guide Compression

How to reduce image file size without losing quality

Practical techniques to make images smaller — resizing, cropping, choosing quality and format — while keeping them sharp. Includes recommended settings.

Read guide Formats

What is a HEIC file and how to open it on any device

Why iPhones save photos as HEIC, how it compares to JPG, and the easiest ways to open or convert HEIC files on Windows, Android and the web.

Read guide Photo sizes

Passport photo size by country: dimensions in mm, inches and pixels

Official passport and visa photo sizes for the USA, UK, EU/Schengen, Canada, India, China and more — with pixel dimensions for printing and online applications.

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