Email CSS & HTML Support

Check CSS and HTML compatibility across 15 email clients. Based on real-world testing data from caniemail.com — 251 features, updated regularly.

Email Clients

Gmail

webmail

Gmail Web

122 supported15 partial

Gmail Android

mobile

Gmail Mobile

82 supported59 partial

Gmail iOS

mobile

Gmail Mobile

84 supported51 partial

Outlook 365

webmail

Outlook Web

137 supported31 partial

Outlook (New)

desktop

Outlook Web

45 supported24 partial

Outlook Classic

desktop

Microsoft Word

45 supported20 partial

Outlook iOS

mobile

Outlook Mobile

150 supported16 partial

Outlook Android

mobile

Outlook Mobile

145 supported12 partial

Apple Mail

desktop

WebKit

234 supported12 partial

Apple Mail iOS

mobile

WebKit

233 supported9 partial

Yahoo Mail

webmail

Yahoo

106 supported26 partial

Samsung Mail

mobile

Samsung

208 supported20 partial

Thunderbird

desktop

Gecko

203 supported4 partial

HEY Mail

webmail

WebKit

165 supported7 partial

Superhuman

desktop

Blink

84 supported5 partial

Features by Category

HTML Elements40

CSS At-Rules5

@font-face @import @keyframes @media @supports

Pseudo-Elements6

::after ::before ::first-letter ::first-line ::marker ::placeholder

Pseudo-Classes & Selectors32

CSS Functions8

calc clamp conic-gradient fit-content linear-gradient max min radial-gradient

CSS Properties160

!important accent-color align-items animation aspect-ratio backdrop-filter background background-blend-mode background-clip background-color background-image background-origin background-position background-repeat background-size bimi block-size border border-collapse border-image border-inline border-inline-individual border-inline-longhand border-radius border-radius-logical border-spacing bottom box-shadow box-sizing caption-side clear clip-path color color-scheme column-count columns css-comments cursor custom-properties direction display display:flex display:grid display:none empty-cells filter flex-direction flex-wrap float font font-family font-kerning font-size font-stretch font-weight gap grid-template-columns height hyphenate-character hyphenate-limit-chars hyphens inline-size inset justify-content left letter-spacing light-dark line-height list-style list-style-image list-style-position list-style-type margin margin-block-start-end margin-inline-block margin-inline-start-end mask-image max-block-size max-height max-inline-size max-width min-block-size min-height min-inline-size min-width mix-blend-mode modern-color nesting object-fit object-position opacity orphans outline outline-offset overflow overflow-wrap padding padding-block-start-end padding-inline-block padding-inline-start-end position resize rgb rgba right scroll-snap shape-margin shape-outside system-ui tab-size table-layout text-align text-align-last text-decoration text-decoration-color text-decoration-line text-decoration-skip-ink text-decoration-style text-decoration-thickness text-emphasis text-emphasis-position text-indent text-justify text-orientation text-overflow text-shadow text-transform text-underline-offset text-underline-position text-wrap top transform transition unit-ch unit-cm unit-em unit-ex unit-in unit-initial unit-mm unit-pc unit-percent unit-pt unit-px unit-rem unit-vh unit-vmax unit-vmin unit-vw user-select vertical-align visibility white-space white-space-collapse widows width word-break word-spacing writing-mode z-index

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