Generally you should use eot, woff, ttf and svg to support all browsers.
Example:
@font-face {
font-family: 'font';
src: url('../fonts/font.eot'); /* IE9 Compat Modes */
src: url('../fonts/font.eot') format('embedded-opentype'), /* IE6-IE8 */
url('../fonts/font.woff') format('woff'), /* Modern Browsers */
url('../fonts/font.ttf') format('truetype'), /* Safari, Android, iOS */
url('../fonts/font.svg#PlanerRegular') format('svg'); /* Legacy iOS */
}