Most Finnish adjectives compare predictably: add -mpi for the comparative and -in for the superlative. But a small set of the most frequent words breaks the pattern — some completely (like English good → better → best), some in a way that merely looks broken because a hidden stem change surfaces. There is no logical shortcut here: these are high-frequency enough that you will meet them daily, so learn the triads by heart. This page gives you the full list.
The one that is truly suppletive: hyvä
hyvä ("good") is the Finnish good → better → best: the three degrees come from unrelated roots. You cannot build *hyvämpi any more than English allows *gooder.
| Base | Comparative | Superlative |
|---|---|---|
| hyvä (good) | parempi (better) | paras (best) |
Tämä kahvila on parempi kuin tuo, mutta torin kahvila on paras.
This café is better than that one, but the market café is the best.
Sain kokeesta paremman arvosanan kuin viime kerralla.
I got a better grade on the test than last time.
Two traps live inside paras. First, it is already a superlative, so *parasin ("bestest") is wrong. Second, it declines on a special stem parhaa-, not on paras-:
| Case | Form | Meaning |
|---|---|---|
| Nominative sg | paras | best |
| Genitive sg | parhaan | of the best |
| Partitive sg | parasta | (partitive) best |
| Inessive sg | parhaassa | in the best |
| Nominative pl | parhaat | the best (ones) |
| Partitive pl | parhaita | (partitive) best ones |
Se oli elämäni parhaita päiviä.
It was one of the best days of my life.
Toivotan sinulle kaikkea parasta!
I wish you all the best!
The ones with a hidden stem change: pitkä, uusi, vanha
These are not suppletive — the endings are the regular -mpi and -in — but the base form hides a stem alternation, so the comparative and superlative look surprising.
| Base | Comparative | Superlative |
|---|---|---|
| pitkä (long/tall) | pidempi ~ pitempi (longer) | pisin (longest) |
| lyhyt (short) | lyhyempi (shorter) | lyhin (shortest) |
| uusi (new) | uudempi (newer) | uusin (newest) |
| vanha (old) | vanhempi (older) | vanhin (oldest) |
pitkä is the wildest: the tk becomes d in the comparative (pidempi) and the whole cluster collapses to s in the superlative (pisin). Both pidempi and pitempi are correct; pidempi dominates in speech.
Kesäpäivät ovat pidempiä kuin talvipäivät.
Summer days are longer than winter days.
Vuoden pisin päivä on juhannuksen aikaan.
The longest day of the year is around Midsummer.
uusi alternates s ~ d ~ s: comparative uudempi has a d (from the stem uute-), but the superlative uusin is back to s.
Naapurilla on uudempi auto kuin meillä.
The neighbour has a newer car than we do.
Mikä on älypuhelinten uusin malli?
What's the newest smartphone model?
vanha deserves a note of its own: its comparative vanhempi is also the everyday word for "parent" (vanhemmat = "parents"), and its superlative vanhin means both "oldest" and "the eldest (child)".
Isoveli on minua vanhempi, mutta serkku on perheen vanhin.
My big brother is older than me, but our cousin is the eldest in the family.
The quantity words: paljon and vähän
The two most common quantity words compare suppletively too, and — because they are adverbs of amount, not adjectives — their comparative and superlative both land in special adverbial forms rather than -mpi / -in:
| Base | Comparative | Superlative |
|---|---|---|
| paljon (much/many) | enemmän (more) | eniten (most) |
| vähän (little/few) | vähemmän (less/fewer) | vähiten (least) |
Nykyään luen enemmän kirjoja mutta vähemmän lehtiä.
These days I read more books but fewer magazines.
Häntä pelottaa eniten julkinen esiintyminen.
What scares him most is public speaking.
Note that these have no base *paljompi or *vähämpi — the comparative enemmän comes from a different root (ene-) entirely, and vähemmän / vähiten trim vähän down. English hides the same suppletion in much → more → most and little → less → least, so the concept is familiar; only the shapes are new.
Kahvia on jäljellä enää vähän, teetä on enemmän.
There's only a little coffee left; there's more tea.
Why you cannot reason your way out of these
Regular comparison is generative: give a learner kylmä and they can produce kylmempi, kylmin without ever having heard them. Suppletion switches roots midway, so no rule connects hyvä to parempi or pitkä to pisin — the link is purely historical. This is exactly why English keeps good/better/best and bad/worse/worst as memorised islands. Treat the Finnish set the same way: a short closed list to drill until automatic. The good news is that it is short — beyond the words above, the semi-irregular paha → pahempi → pahin ("bad → worse → worst") is about the last one you need, and almost everything else in the language is regular.
Common Mistakes
❌ Tämä on hyvämpi kuin tuo.
Incorrect — 'good' is suppletive: parempi, never *hyvämpi.
✅ Tämä on parempi kuin tuo.
This one is better than that one.
❌ Se oli päivän parasin hetki.
Incorrect — paras is already a superlative; *parasin doesn't exist.
✅ Se oli päivän paras hetki.
It was the best moment of the day.
❌ Ostin parasin lahjan kaupasta.
Incorrect — paras declines on parhaa-: parhaan lahjan.
✅ Ostin parhaan lahjan kaupasta.
I bought the best gift in the shop.
❌ Kesällä on pitkämpiä päiviä.
Incorrect — the comparative of pitkä is pidempi (pitempi): pidempiä päiviä.
✅ Kesällä on pidempiä päiviä.
In summer the days are longer.
❌ Luen nykyään paljon kuin ennen.
Incorrect — the comparative of paljon is enemmän: enemmän kuin ennen.
✅ Luen nykyään enemmän kuin ennen.
These days I read more than before.
Key Takeaways
- Truly suppletive: hyvä → parempi → paras — and paras declines on parhaa- (parhaan, parasta, parhaat), never adds another -in.
- Hidden stem changes: pitkä → pidempi ~ pitempi → pisin, lyhyt → lyhyempi → lyhin, uusi → uudempi → uusin, vanha → vanhempi → vanhin.
- Quantity words: paljon → enemmän → eniten, vähän → vähemmän → vähiten — adverbial, no base -mpi / -in.
- These are a short closed list with no rule behind them — drill them like English good/better/best.
Now practice Finnish
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Start learning Finnish→Related Topics
- The Comparative -mpi: 'more'A2 — Finnish builds the comparative with the suffix -mpi on the adjective stem: iso → isompi, vanha → vanhempi, kaunis → kauniimpi, hyvä → parempi.
- The Superlative -in: 'most'A2 — Finnish builds the superlative with the suffix -in on the adjective stem: iso → isoin, vanha → vanhin, kaunis → kaunein, hyvä → paras (best).
- Saying 'than': kuin and the Partitive of ComparisonB1 — Finnish says 'than' two ways: kuin + nominative (pidempi kuin minä) or the partitive of comparison with no kuin (minua pidempi).
- Comparative Stem Changes: -mpi → -mma-B1 — When the comparative inflects, -mpi becomes -mma-/-mmä- in most cases (isomman, isommassa), but the partitive keeps the strong -mp- (isompaa).