You can use a set of 400+ icons from Font Awesome
<i class="fa fa-heart"></i> fa-heart
Result: fa-heart
fa-adjust[]
fa-adn[]
fa-align-center[]
fa-align-justify[]
fa-align-left[]
fa-align-right[]
fa-ambulance[]
fa-anchor[]
fa-android[]
fa-angle-double-down[]
fa-angle-double-left[]
fa-angle-double-right[]
fa-angle-double-up[]
fa-angle-down[]
fa-angle-left[]
fa-angle-right[]
fa-angle-up[]
fa-apple[]
fa-archive[]
fa-arrow-circle-down[]
fa-arrow-circle-left[]
fa-arrow-circle-o-down[]
fa-arrow-circle-o-left[]
fa-arrow-circle-o-right[]
fa-arrow-circle-o-up[]
fa-arrow-circle-right[]
fa-arrow-circle-up[]
fa-arrow-down[]
fa-arrow-left[]
fa-arrow-right[]
fa-arrow-up[]
fa-arrows[]
fa-arrows-alt[]
fa-arrows-h[]
fa-arrows-v[]
fa-asterisk[]
fa-automobile(alias) []
fa-backward[]
fa-ban[]
fa-bank(alias) []
fa-bar-chart-o[]
fa-barcode[]
fa-bars[]
fa-beer[]
fa-behance[]
fa-behance-square[]
fa-bell[]
fa-bell-o[]
fa-bitbucket[]
fa-bitbucket-square[]
fa-bitcoin(alias) []
fa-bold[]
fa-bolt[]
fa-bomb[]
fa-book[]
fa-bookmark[]
fa-bookmark-o[]
fa-briefcase[]
fa-btc[]
fa-bug[]
fa-building[]
fa-building-o[]
fa-bullhorn[]
fa-bullseye[]
fa-cab(alias) []
fa-calendar[]
fa-calendar-o[]
fa-camera[]
fa-camera-retro[]
fa-car[]
fa-caret-down[]
fa-caret-left[]
fa-caret-right[]
fa-caret-square-o-down[]
fa-caret-square-o-left[]
fa-caret-square-o-right[]
fa-caret-square-o-up[]
fa-caret-up[]
fa-certificate[]
fa-chain(alias) []
fa-chain-broken[]
fa-check[]
fa-check-circle[]
fa-check-circle-o[]
fa-check-square[]
fa-check-square-o[]
fa-chevron-circle-down[]
fa-chevron-circle-left[]
fa-chevron-circle-right[]
fa-chevron-circle-up[]
fa-chevron-down[]
fa-chevron-left[]
fa-chevron-right[]
fa-chevron-up[]
fa-child[]
fa-circle[]
fa-circle-o[]
fa-circle-o-notch[]
fa-circle-thin[]
fa-clipboard[]
fa-clock-o[]
fa-cloud[]
fa-cloud-download[]
fa-cloud-upload[]
fa-cny(alias) []
fa-code[]
fa-code-fork[]
fa-codepen[]
fa-coffee[]
fa-cog[]
fa-cogs[]
fa-columns[]
fa-comment[]
fa-comment-o[]
fa-comments[]
fa-comments-o[]
fa-compass[]
fa-compress[]
fa-copy(alias) []
fa-credit-card[]
fa-crop[]
fa-crosshairs[]
fa-css3[]
fa-cube[]
fa-cubes[]
fa-cut(alias) []
fa-cutlery[]
fa-dashboard(alias) []
fa-database[]
fa-dedent(alias) []
fa-delicious[]
fa-desktop[]
fa-deviantart[]
fa-digg[]
fa-dollar(alias) []
fa-dot-circle-o[]
fa-download[]
fa-dribbble[]
fa-dropbox[]
fa-drupal[]
fa-edit(alias) []
fa-eject[]
fa-ellipsis-h[]
fa-ellipsis-v[]
fa-empire[]
fa-envelope[]
fa-envelope-o[]
fa-envelope-square[]
fa-eraser[]
fa-eur[]
fa-euro(alias) []
fa-exchange[]
fa-exclamation[]
fa-exclamation-circle[]
fa-exclamation-triangle[]
fa-expand[]
fa-external-link[]
fa-external-link-square[]
fa-eye[]
fa-eye-slash[]
fa-facebook[]
fa-facebook-square[]
fa-fast-backward[]
fa-fast-forward[]
fa-fax[]
fa-female[]
fa-fighter-jet[]
fa-file[]
fa-file-archive-o[]
fa-file-audio-o[]
fa-file-code-o[]
fa-file-excel-o[]
fa-file-image-o[]
fa-file-movie-o(alias) []
fa-file-o[]
fa-file-pdf-o[]
fa-file-photo-o(alias) []
fa-file-picture-o(alias) []
fa-file-powerpoint-o[]
fa-file-sound-o(alias) []
fa-file-text[]
fa-file-text-o[]
fa-file-video-o[]
fa-file-word-o[]
fa-file-zip-o(alias) []
fa-files-o[]
fa-film[]
fa-filter[]
fa-fire[]
fa-fire-extinguisher[]
fa-flag[]
fa-flag-checkered[]
fa-flag-o[]
fa-flash(alias) []
fa-flask[]
fa-flickr[]
fa-floppy-o[]
fa-folder[]
fa-folder-o[]
fa-folder-open[]
fa-folder-open-o[]
fa-font[]
fa-forward[]
fa-foursquare[]
fa-frown-o[]
fa-gamepad[]
fa-gavel[]
fa-gbp[]
fa-ge(alias) []
fa-gear(alias) []
fa-gears(alias) []
fa-gift[]
fa-git[]
fa-git-square[]
fa-github[]
fa-github-alt[]
fa-github-square[]
fa-gittip[]
fa-glass[]
fa-globe[]
fa-google[]
fa-google-plus[]
fa-google-plus-square[]
fa-graduation-cap[]
fa-group(alias) []
fa-h-square[]
fa-hacker-news[]
fa-hand-o-down[]
fa-hand-o-left[]
fa-hand-o-right[]
fa-hand-o-up[]
fa-hdd-o[]
fa-header[]
fa-headphones[]
fa-heart[]
fa-heart-o[]
fa-history[]
fa-home[]
fa-hospital-o[]
fa-html5[]
fa-image(alias) []
fa-inbox[]
fa-indent[]
fa-info[]
fa-info-circle[]
fa-inr[]
fa-instagram[]
fa-institution(alias) []
fa-italic[]
fa-joomla[]
fa-jpy[]
fa-jsfiddle[]
fa-key[]
fa-keyboard-o[]
fa-krw[]
fa-language[]
fa-laptop[]
fa-leaf[]
fa-legal(alias) []
fa-lemon-o[]
fa-level-down[]
fa-level-up[]
fa-life-bouy(alias) []
fa-life-ring[]
fa-life-saver(alias) []
fa-lightbulb-o[]
fa-link[]
fa-linkedin[]
fa-linkedin-square[]
fa-linux[]
fa-list[]
fa-list-alt[]
fa-list-ol[]
fa-list-ul[]
fa-location-arrow[]
fa-lock[]
fa-long-arrow-down[]
fa-long-arrow-left[]
fa-long-arrow-right[]
fa-long-arrow-up[]
fa-magic[]
fa-magnet[]
fa-mail-forward(alias) []
fa-mail-reply(alias) []
fa-mail-reply-all(alias) []
fa-male[]
fa-map-marker[]
fa-maxcdn[]
fa-medkit[]
fa-meh-o[]
fa-microphone[]
fa-microphone-slash[]
fa-minus[]
fa-minus-circle[]
fa-minus-square[]
fa-minus-square-o[]
fa-mobile[]
fa-mobile-phone(alias) []
fa-money[]
fa-moon-o[]
fa-mortar-board(alias) []
fa-music[]
fa-navicon(alias) []
fa-openid[]
fa-outdent[]
fa-pagelines[]
fa-paper-plane[]
fa-paper-plane-o[]
fa-paperclip[]
fa-paragraph[]
fa-paste(alias) []
fa-pause[]
fa-paw[]
fa-pencil[]
fa-pencil-square[]
fa-pencil-square-o[]
fa-phone[]
fa-phone-square[]
fa-photo(alias) []
fa-picture-o[]
fa-pied-piper[]
fa-pied-piper-alt[]
fa-pied-piper-square(alias) []
fa-pinterest[]
fa-pinterest-square[]
fa-plane[]
fa-play[]
fa-play-circle[]
fa-play-circle-o[]
fa-plus[]
fa-plus-circle[]
fa-plus-square[]
fa-plus-square-o[]
fa-power-off[]
fa-print[]
fa-puzzle-piece[]
fa-qq[]
fa-qrcode[]
fa-question[]
fa-question-circle[]
fa-quote-left[]
fa-quote-right[]
fa-ra(alias) []
fa-random[]
fa-rebel[]
fa-recycle[]
fa-reddit[]
fa-reddit-square[]
fa-refresh[]
fa-renren[]
fa-reorder(alias) []
fa-repeat[]
fa-reply[]
fa-reply-all[]
fa-retweet[]
fa-rmb(alias) []
fa-road[]
fa-rocket[]
fa-rotate-left(alias) []
fa-rotate-right(alias) []
fa-rouble(alias) []
fa-rss[]
fa-rss-square[]
fa-rub[]
fa-ruble(alias) []
fa-rupee(alias) []
fa-save(alias) []
fa-scissors[]
fa-search[]
fa-search-minus[]
fa-search-plus[]
fa-send(alias) []
fa-send-o(alias) []
fa-share[]
fa-share-alt[]
fa-share-alt-square[]
fa-share-square[]
fa-share-square-o[]
fa-shield[]
fa-shopping-cart[]
fa-sign-in[]
fa-sign-out[]
fa-signal[]
fa-sitemap[]
fa-skype[]
fa-slack[]
fa-sliders[]
fa-smile-o[]
fa-sort[]
fa-sort-alpha-asc[]
fa-sort-alpha-desc[]
fa-sort-amount-asc[]
fa-sort-amount-desc[]
fa-sort-asc[]
fa-sort-desc[]
fa-sort-down(alias) []
fa-sort-numeric-asc[]
fa-sort-numeric-desc[]
fa-sort-up(alias) []
fa-soundcloud[]
fa-space-shuttle[]
fa-spinner[]
fa-spoon[]
fa-spotify[]
fa-square[]
fa-square-o[]
fa-stack-exchange[]
fa-stack-overflow[]
fa-star[]
fa-star-half[]
fa-star-half-empty(alias) []
fa-star-half-full(alias) []
fa-star-half-o[]
fa-star-o[]
fa-steam[]
fa-steam-square[]
fa-step-backward[]
fa-step-forward[]
fa-stethoscope[]
fa-stop[]
fa-strikethrough[]
fa-stumbleupon[]
fa-stumbleupon-circle[]
fa-subscript[]
fa-suitcase[]
fa-sun-o[]
fa-superscript[]
fa-support(alias) []
fa-table[]
fa-tablet[]
fa-tachometer[]
fa-tag[]
fa-tags[]
fa-tasks[]
fa-taxi[]
fa-tencent-weibo[]
fa-terminal[]
fa-text-height[]
fa-text-width[]
fa-th[]
fa-th-large[]
fa-th-list[]
fa-thumb-tack[]
fa-thumbs-down[]
fa-thumbs-o-down[]
fa-thumbs-o-up[]
fa-thumbs-up[]
fa-ticket[]
fa-times[]
fa-times-circle[]
fa-times-circle-o[]
fa-tint[]
fa-toggle-down(alias) []
fa-toggle-left(alias) []
fa-toggle-right(alias) []
fa-toggle-up(alias) []
fa-trash-o[]
fa-tree[]
fa-trello[]
fa-trophy[]
fa-truck[]
fa-try[]
fa-tumblr[]
fa-tumblr-square[]
fa-turkish-lira(alias) []
fa-twitter[]
fa-twitter-square[]
fa-umbrella[]
fa-underline[]
fa-undo[]
fa-university[]
fa-unlink(alias) []
fa-unlock[]
fa-unlock-alt[]
fa-unsorted(alias) []
fa-upload[]
fa-usd[]
fa-user[]
fa-user-md[]
fa-users[]
fa-video-camera[]
fa-vimeo-square[]
fa-vine[]
fa-vk[]
fa-volume-down[]
fa-volume-off[]
fa-volume-up[]
fa-warning(alias) []
fa-wechat(alias) []
fa-weibo[]
fa-weixin[]
fa-wheelchair[]
fa-windows[]
fa-won(alias) []
fa-wordpress[]
fa-wrench[]
fa-xing[]
fa-xing-square[]
fa-yahoo[]
fa-yen(alias) []
fa-youtube[]
fa-youtube-play[]
fa-youtube-square[]