|Passport picture size||Width: 900pixel, Height: 1200pixel|
|Required Size in Kilobytes||From: 50 to: 10240|
|Image definition parameters||Head height (up to the top of the hair): 55%; Distance from top the of the photo to the top of the hair: 15%|
|Suitable for online submission?||Yes|
|Web links to official documents||https://www.gov.uk/get-a-child-passport|
At least 600 pixels wide and 750 pixels tall; At least 50KB and no more than 10MB
Do not worry about the photo size requirements. Visafoto.com guarantees compliance. It makes correct photos and fixes background.