Brand image sizes for the web

images.md

Icons

16x16px Favicon base
24x24px Pinned site in IE9
29x29 iOS Settings icon (non-Retina)
32x32px New tab page in IE, Windows 7+ tasbar and Safari’s ‘Read Later’ sidebar
50x50px iOS Spotlight result icon (non-Retina)
57x57px iOS home screen icon (iPod Touch, iPhone to 3G)
58x58px iOS Settings icon (Retina)
72x72px iPad home screen icon (iPad 1 & 2)
96x96px GoogleTV
100x100px iOS Spotlight result icon (Retina)
114x114px iPhone Retina home screen icon (iPhone 4+)
128x128px Chrome Web Store
195x195px Opera Speed Dial

Social Media

Facebook

logo 180x180px
cover 851x315px
application 111x74px
event 714x264px
post normal 403x403px
post highlight 843x403px

Twitter

profile 240x240px
header 1252x626px
background 2048x1707px

YouTube

profile 200x200px
background 1600x1000px

Google+

profile 250x250px
background full 2120x1192px
background HD 1920x1080px

Flickr

icon 48x48px
profile 300x300px
cover 2048x492px (cropped to 234px height) full explanation

Vimeo

profile 300x300px
16/9 thumbnail 960x540px
4/3 thumbnail 720x540px

Pinterest

profile 48x48px

Skype

profile 214x214px

Tumblr

profile 64x64px

LinkedIn

profile 200x200px
logo 120x60px
logo small 50x50px
banner 640x220px

Gravatar

profile 420x420px

Slideshare

profile 96x96px

Foursquare

profile 128x128px

About.me

background 1680x1050px

Believe.in

profile 400x400px
background 1980x1080px

JustGiving

logo 195x68px
appeal module 435x162px
appeal page logo 142x63px
background 1600x1200px
why we care 442x279px