1 one · 2 two · 3 three · 4 four · 5 five 6 six · 7 seven · 8 eight · 9 nine · 10 ten 11 eleven · 12 twelve · 13 thirteen · 14 fourteen · 15 fifteen 16 sixteen · 17 seventeen · 18 eighteen · 19 nineteen · 20 twenty Tip: 13–19 end with -teen 20 is different → twenty