How to Count in Spanish
To count in Spanish, first master the Spanish words for 0 through 10, since they form the basis of many larger numbers. Then, learn the numbers 11 through 19, which are either derived from their single digit counterparts, or a combination of the word for 10 plus their single digit counterparts. For example, you can learn that 2 in Spanish is “dos” and 12 in Spanish is “doce,” which is a derivation of “dos.” You can also figure out that 17 in Spanish, which is “diecisiete,” is a combination of the Spanish words for 10, “diez,” and 7, “siete.”
Use the word cero (SAY-roh) for "zero. " When counting to 10, you don't typically start with zero. The word for "zero" in Spanish sounds somewhat similar to the English word, so it should be pretty easy to remember. As in English, the number cero stands alone and does not form the base of any other numbers. However, it's still an important number to know. It could come in handy if, for example, you were reading out a phone number or credit card number in Spanish. Start by counting from 1 to 5. You likely know at least the first few numbers from various songs or TV shows, so counting to 5 in Spanish should be relatively easy. Memorize these words, since they form the basis for constructing the words for larger numbers. One (1) is uno (OO-noh). Two (2) is dos (dohs). Three (3) is tres (trehs). Four (4) is cuatro (KWAHT-roh). Five (5) is cinco (SEENK-oh). Move on to the words for the numbers 6 through 10. Once you can count from 1 to 5 smoothly and easily, add the numbers from 6 to 10 to your vocabulary. Practice them separately as new numbers until they roll off your tongue as easily as 1 to 5 did. Six (6) is seis (saiss) Seven (7) is siete (SEE-yeht-ay). Eight (8) is ocho (OHCH-oh). Nine (9) is nueve (NOO-ay-veh). Ten (10) is diez (DEE-ehss). Memorize the words for the numbers 11 through 15. As with the words for the numbers 0 through 10, the numbers from 11 through 15 have their own unique words in Spanish. However, they do bear some relation to the words for numbers 1 through 9, so they're a little easier to learn once you know how to count to 10. Eleven (11) is once (OHN-say). Twelve (12) is doce (DOH-say). Thirteen (13) is trece (TRAY-say). Fourteen (14) is catorce (KAH-tor-say). Fifteen (15) is quince (KEEN-say). Start the formula for forming numbers with numbers 16 through 19. Sixteen (16) is dieciséis (DEE-ay-see-SAYS). Note the accent mark over the e , which indicates to place emphasis on the last syllable. Seventeen (17) is diecisiete (DEE-ay-see-SEE-yeht-ay). Eighteen (18) is dieciocho (DEE-ay-see-OHCH-oh). Nineteen (19) is diecinueve (DEE-ay-see-NOO-ay-veh). Try counting by tens to construct other numbers. With the exception of 10 and 20, all words for numbers in the tens spot are constructed by adding the suffix -ta to a form of the work for the multiplier digit. Twenty (20) is veinte (VEE-ehn-tay). Thirty (30) is treinta (TRAY-ehn-tah). Forty (40) is cuarenta (kwah-RAYN-tah). Fifty (50) is cincuenta (seen-KWEH-yen-tah). Sixty (60) is sesenta (say-SAYN-tah). Seventy (70) is setenta (say-TAYN-tah). Eighty (80) is ochenta (oh-CHAYN-tah). Ninety (90) is noventa (noh-BAYN-tah). Note that the Spanish v is pronounced differently than the English v. It sounds more similar to the way the English b is pronounced. Combine viente with the number in the ones place to form the words for numbers 21-29. To form other numbers through 99 in Spanish, you typically use the word y to connect the number in the ones place with the number in the tens place. However, for the numbers from 21 through 29, you simply combine the two words together into one word. Twenty-one (21) is veintiuno (VEE-ehn-tee-OO-noh). Twenty-two (22) is veintidós (VEE-ehn-tee-DOHS). Twenty-three (23) is veintitrés (VEE-ehn-tee-TREHS). Twenty-four (24) is veinticuatro (VEE-ehn-tee-KWAHT-roh). Twenty-five (25) is veinticinco (VEE-ehn-tee-SEENK-oh). Twenty-six (26) is veintiséis (VEE-ehn-tee-SAYS). Twenty-seven (27) is veintisiete (VEE-ehn-tee-SEE-yeht-ay). Twenty-eight (28) is veintiocho (VEE-ehn-tee-OHCH-oh). Twenty-nine (29) is veintinueve (VEE-ehn-tee-NOO-ay-veh). Use the word y to form the rest of the numbers through 99. In Spanish, y (pronounced ee ) means "and." Since you know how to count to 10 and you also know how to count by tens, you can now say every number from 1 to 99 in Spanish. Simply say the digit in the ones place followed by the word y , then the name of the tens place number. For example, thirty-one (31) is treinta y uno. Seventy-five (75) is setenta y cinco. Ninety-seven (97) is noventa y siete. Keep practicing by making your own combinations. You might write down a series of numbers and then read each one in Spanish. Use cien (SEE-ehn) for the number 100 and all other hundreds. Cien forms the base for all other numbers from 101 to 999. You'll only use cien when referring to the specific number 100, however. When combining it with other numbers, add the suffix -tos to the end of the root. For other hundreds, use the word for the multiplier digit (or a variation thereof) combined with cientos. One hundred (100) is ciento (SEE-ehn-toh) when there are other numbers present. For example, you would read the number 103 as ciento tres. Two hundred (200) is doscientos (DOHS-see-EHN-tohs). Three hundred (300) is trescientos (TRAYS-see-EHN-tohs). Four hundred (400) is cuatrocientos (KWAHT-roh-SEE-ehn-tohs). Five hundred (500) is quinientos (KEEN-ee-EHN-tohs). Note that this form is slightly irregular. The irregularity avoids confusion with quince (15). Six hundred (600) is seiscientos (SAYS-see-EHN-tohs). Seven hundred (700) is setecientos (SEH-tay-SEE-ehn-tohs). Note that this form is also slightly irregular. Eight hundred (800) is ochocientos (OHCH-oh-SEE-ehn-tohs). Nine hundred (900) is novecientos (NOH-veh-SEE-ehn-tohs). Note that this form is also slightly irregular. List the numbers in the tens and ones places to form the words for numbers from 101 to 999. Now that you know the words for all the hundreds, tens, and ones, you can start combining those words to name larger numbers. Use an y before the number in the ones place, but not between the numbers in the tens and hundreds places. For example, 285 is doscientos ochenta y cinco. 872 is ochocientos sentient y dos. As with the numbers in the tens, write down a random list of numbers to practice saying them in Spanish. Memorize the word mil (meel) to say the words for numbers from 1000 through 9999. For one thousand, use mil (meel) by itself. For the remaining thousands, use the cardinal number of the multiplier followed by the word mil. For example, two thousand (2000) would be dos mil. Words for numbers in the thousands follow the same pattern or formula you learned to create numbers in the tens and hundreds. If you want to go into tens of thousands and hundreds of thousands, use the word for the tens or hundreds followed by the word mil. For example, 800,000 would be ochocientos mil. Follow the thousands' formula for millions and billions. One million (1,000,000) in Spanish is un millón (1.000.000) (oon mee-YOHN). One billion in Spanish is mil millones (meel mee-YOHN-ays), or one thousand million. This is because the Spanish use what is called the long scale system. This system alternates between a scale word and its thousand when naming large numbers. There is the word un billón in Spanish, which sounds like the word "billion" in English. However, this word refers to a million millions, or 1,000,000,000,000. 
Use the word cero (SAY-roh) for "zero. Start by counting from 1 to 5. Move on to the words for the numbers 6 through 10. Memorize the words for the numbers 11 through 15. Start the formula for forming numbers with numbers 16 through 19. Try counting by tens to construct other numbers. Combine viente with the number in the ones place to form the words for numbers 21-29. Use the word y to form the rest of the numbers through 99. Use cien (SEE-ehn) for the number 100 and all other hundreds. List the numbers in the tens and ones places to form the words for numbers from 101 to 999. Memorize the word mil (meel) to say the words for numbers from 1000 through 9999. Follow the thousands' formula for millions and billions. 