| # | Cardinal number | Ordinal number |
|---|---|---|
| 0 | nolla | nollas |
| 1 | yksi | ensimmäinen |
| 2 | kaksi | toinen |
| 3 | kolme | kolmas |
| 4 | neljä | neljäs |
| 5 | viisi | viides |
| 6 | kuusi | kuudes |
| 7 | seitsemän | seitsemäs |
| 8 | kahdeksan | kahdeksas |
| 9 | yhdeksän | yhdeksäs |
| 10 | kymmenen | kymmenes |
The cardinal numbers from 11 to 19 are composed with suffix -toista (“-teen”): yksitoista, kaksitoista...
The cardinal numbers from 20 to 99 are composed according to the pattern (kaksi—yhdeksän) + kymmentä + (yksi—yhdeksän).
Hundreds are simply added to the same set, one hundred in nominative and the hundreds of two hundred—nine hundred in partitive.
The ordinal numbers from 11th to 19th are the ordinal numbers 1st to 9th with suffix -toista (“-teen”), with 11th and 12th being exceptions: yhdestoista, kahdestoista, kolmastoista...
The ordinal numbers from 20th to 99th are the cardinal numbers with all components receiving the ordinal suffix:
kahdes is used with the decades and, it may also, alongside yhdes, optionally be used for units. For example, both kahdeskymmenesensimmäinen and kahdeskymmenesyhdes are acceptable, likewise for kahdeskymmenestoinen and kahdeskymmeneskahdes.
The same pattern continues for higher numerals, with all components receiving the suffix.
Numbers from 21 to 99 (except for the tens 30s, 40s, etc.) used to be formed as the unit (either in cardinal or ordinal) followed by the partitive singular form of the ordinal of the next number in tens, similar to how 11 to 19 is formed as 1-9 + toista (“of the second”). Thus, 21 used to be yksikolmatta (yksi (“of”) + kolmatta (“of the third”)), while 21st would have been yhdeskolmatta or ensimmäinenkolmatta (yhdes/ensimmäinen (“first”) + kolmatta (“of the third”)). These forms have fallen out of use and are now considered archaic.
Etymologically all of these forms, including 11–19, are by ellipsis; the word kymmentä (“(of) decade”) is left out. For example, yksitoista (“eleven”, literally “one of the second”) was originally yksi toista kymmentä (literally “one of the second decade”).
The digits 1-9 also have their own names. They are used to refer to the digits as opposed to the numbers, but also used colloquially to refer to certain numbers that are largely departed from the corresponding quantities, such as bus route numbers. In such cases, only the final digit in the number is referred to by its digit name. These forms are shown in the full table under "digit name".
In colloquial Finnish, the digit names seiska for 7, kasi for 8 and ysi for 9 are the overwhelmingly most common options, and the corresponding standard words like seitsemäinen are very rare.
Numbers which end in zeros tend to be referred to by a name that corresponds closer to the value, e.g. 50 is usually viisikymppinen, not viisinolla (but e.g. 51 is viisiykkönen, not *viisikymppiäykkönen), and 200 is usually kaksisatanen, not kaksinollanolla. nolla may be used for intermediate digits, so 501 would be viisinollaykkönen.
In colloquial Finnish, special forms of the cardinal numbers are often used when counting things. They are not used in other contexts, such as to refer to the number of things outside of counting, or when reciting e.g. phone numbers.
For numbers 1-7, the words are derived from the proper word by taking the initial consonants, if any, and the vowels of the first syllable, and making the vowel long if it is short. Note, however:
Exact tens or decades generally use the same form as they would in other contexts too in colloquial Finnish, e.g. ten is simply kymppi. This also means that later decades, e.g. 20 are often reduced significantly, e.g. -kymmentä to -kyt. Counting forms of numbers 11-19 are the same as those for 1-9 with the suffix -too, reduced from -toista according to the usual rules. Numbers like 21 (i.e. not an exact decade, but greater than 20) are generally pronounced as if they were separate digits.
For example, these are the colloquial counting forms of numbers from 1 to 24 (the exact forms may vary by speaker). Forms used more generally than just when counting are marked with an asterisk:
When written in numeric form, cardinal numbers are divided in "groups of three" with spaces: 1,000,000,000 → 1 000 000 000. The space is non-breaking and the numeral may not be split into separate lines. Instead of a decimal point, there is a desimaalipilkku (“decimal comma”) (e.g. 1,5).
When writing a cardinal number out as text, each "group of three" is written together as one word, separated with a space from the powers of ten (tuhatta, miljoonaa, miljardia...):
Ordinals are usually abbreviated as the number followed by a period or full stop, (e.g. 1. 2. 3. 39.). An alternative is to write the numeral followed by the corresponding ordinal number ending :nen (for ensimmäinen, toinen) or :s (other numerals), which can then be inflected (unlike the two aforementioned forms), e.g. 1:nen, 1000:s (genitive singular forms: 1:sen, 1000:nnen). This form is used when the inflectional ending is not clear from context (e.g. indicated by the following word) or if the numeral is at the end of a sentence to avoid a double period. Furthermore, in the names of monarchs, popes or other dignitaries, the Roman numerals are used (without a period).
For example, the ordinal kolmas is abbreviated either as 3. or 3:s, or in the names of monarchs, popes or other dignitaries, as III. Both 21:nen (kahdeskymmenesensimmäinen) or 21:s (kahdeskymmenesyhdes) are valid abbreviations for the ordinal of 21.
Contrary to the spelling, all powers of ten (and their multipliers) get their own primary stress. For example, kuusisataaseitsemänkymmentäneljä is pronounced as if kuusisataa seitsemänkymmentä neljä (IPA(key): /ˈkuːsiˌsɑtɑː ˈsei̯tsemænˌkymːentæ ˈneljæ/). The last term (e.g. the units place) is usually given somewhat more stress.
With a numeral other than yksi (“one”) in the nominative case, the main word is in partitive case. In other cases, the cardinal number and the word it defines are congruent:
In the above case, the accusative case of a numeral is always equivalent in form to the nominative case, never the genitive:
(not **näin kahden koiraa)
When something quantified with a numeral is used as the subject of a verb, the verb is usually in the singular regardless of the quantity. However, when the number is greater than one, it may also be in the plural to express definiteness:
The plural forms are used mainly with words that are used only in plural:
It may also be used otherwise to mark definiteness, often in reference to a set of things.
All the declinable parts of a number are in the same case:
When the number is written in numeric form, the case suffix of the last declinable part is added to the number with a colon. However, the case ending is not written if it is clear from context, e.g. when indicated by the following word:
With abbreviations or symbols, the case ending can likewise be written after the 'unit', but is never written when it is a partitive singular form only because the numeral is in the nominative (if the numeral is in the partitive, it is written):
Inexact quantities may always be expressed with the adverb noin (“about”). The numbers 3 to 10 have also a specific inexact form, which is formed with the suffix -isen: kolmisen, nelisen, viitisen, kuutisen, seitsemisen, kahdeksisen, yhdeksisen, kymmenisen. They may be combined with -toista, kymmentä, sataa etc. for larger quantities, e.g. viitisen miljoonaa (~5,000,000). The corresponding form for kaksi is parisen. It behaves otherwise similarly, but cannot be combined with -toista. Some other quantities have their own word, e.g. tusina (“dozen”) may be used for "about twelve" (as tusinan verran is usually interpreted).
The number of repetitions may always be expressed with kertaa (“times”). The numbers 2 to 10 plus 100, 1.000 and 1.000.000 have also a specific repetitive form which is formed with suffix -sti: kahdesti, kolmasti, neljästi, viidesti, kuudesti, seitsemästi, kahdeksasti, yhdeksästi, kymmenesti, sadasti, tuhannesti, miljoonasti. They may be combined with -toista, kymmentä, sataa etc. for larger quantities.
The numbers 2 to 6 have adverbial forms that express how many people are present or acting in unison: kaksin/kahdestaan, kolmisin/kolmistaan, neljästään/nelistään, viidestään, kuudestaan.