"To open" is the aspect pair otvírat (imperfective) / otevřít (perfective). It is one of the harder high-frequency pairs because the two halves do not just differ in length — they sit in different conjugation classes and the perfective hides the notoriously difficult Czech consonant ř. Worse, the imperfective stem is otví- while the perfective stem is otev-, so the two verbs barely look related. This page lays both paradigms out cleanly and flags every trap.
A note on the imperfective: otvírat vs otevírat
The imperfective has two accepted shapes: otvírat and otevírat. They mean exactly the same thing and conjugate identically (just with or without the -e-). otvírat is the more common spoken form; otevírat is equally correct and slightly fuller. We use otvírat as the headword below; substitute the extra -e- anywhere if you prefer.
The two halves, conjugated side by side
The imperfective otvírat is a regular Class V (-á-) verb — it patterns like dělat. The perfective otevřít is a Class I (-e-) verb built on the present stem otevř-, ending in the consonant cluster -vř-.
| Person | otvírat (imperfective) | otevřít (perfective) |
|---|---|---|
| já | otvírám | otevřu |
| ty | otvíráš | otevřeš |
| on / ona / ono | otvírá | otevře |
| my | otvíráme | otevřeme |
| vy | otvíráte | otevřete |
| oni / ony | otvírají | otevřou |
The two stems: otví- vs otev-
The single most confusing thing about this pair is that the imperfective and perfective use different stems that share almost no letters:
- Imperfective stem otví-: otvírám, otvíral, otvírej.
- Perfective stem otev- (plus ř): otevřu, otevřel, otevři.
So you cannot derive one from the other by ear. Store both halves as a fixed pair: otvírat / otevřít, the way you'd store an irregular English pair like "buy / bought."
Present meaning vs. future meaning
Otvírám is a real present — opening now or habitually. Otevřu, despite its present-tense endings, points to the future, because a perfective cannot occupy the unfinished present moment.
Obchod otvírají v devět a zavírají v šest.
The shop opens at nine and closes at six.
Počkej, otevřu ti, mám klíče.
Wait, I'll open up for you, I've got the keys.
Proč otvíráš okno, vždyť je zima?
Why are you opening the window, it's cold out?
The first sentence is a daily routine (imperfective); the second is a single act about to happen (perfective future). You could not say otevřu for the habitual opening hours, nor otvírám for the one-off "I'll let you in."
What the verb governs: the accusative
Both verbs are straightforwardly transitive: the thing opened stands in the accusative.
Otevři okno, prosím, je tu dusno.
Open the window, please, it's stuffy in here.
Nikdy neotvírej dveře cizím lidem.
Never open the door to strangers.
In both, okno and dveře are accusative direct objects. (dveře "door" is plural-only in Czech, but still simply the accusative object.)
The past tense
Both build the past from the l-participle plus the auxiliary, agreeing in gender and number. The aspect difference holds: otvíral jsem = "I was opening / used to open"; otevřel jsem = "I opened (and it's open now)."
| Subject | otvírat | otevřít |
|---|---|---|
| masc. sg. | otvíral jsem | otevřel jsem |
| fem. sg. | otvírala jsem | otevřela jsem |
| masc. anim. pl. | otvírali jsme | otevřeli jsme |
| fem. pl. | otvíraly jsme | otevřely jsme |
Ráno jsem otvíral všechna okna, aby se vyvětralo.
In the morning I kept opening all the windows to air the place out.
Otevřel jsem dopis a hned mi bylo jasno.
I opened the letter and it was immediately clear to me.
The first paints a repeated morning activity; the second reports one decisive act with a result. Same English "opened," two different Czech verbs.
The future and the imperative
The future and imperative split by aspect, as always:
- Imperfective future: budu otvírat, budeš otvírat… — opening as a repeated or ongoing future activity.
- Perfective future: just otevřu — no budu.
- Imperative: perfective otevři / otevřete (open it, one act), imperfective otvírej / otvírejte (keep opening, or in negatives).
| otvírat | otevřít | |
|---|---|---|
| ty | otvírej | otevři |
| my | otvírejme | otevřeme |
| vy | otvírejte | otevřete |
Od září budeme otvírat už v sedm ráno.
From September we'll be opening at seven in the morning.
Neotvírej to, je to překvapení!
Don't open it, it's a surprise!
The antonym pair: zavírat / zavřít
Learn otvírat / otevřít together with its opposite, zavírat / zavřít ("to close"). They pattern identically — perfective Class I with ř (zavřu, zavřeš…), imperfective Class V (zavírám) — so mastering one gives you the other almost for free.
Otevřu okno na chvíli a pak ho zase zavřu.
I'll open the window for a moment and then close it again.
Common Mistakes
❌ Teď otevřu okno.
Incorrect if you mean now — otevřu is future, not present.
✅ Teď otvírám okno.
I'm opening the window now.
❌ Zítra budu otevřít obchod.
Incorrect — a perfective never combines with budu.
✅ Zítra otevřu obchod.
Tomorrow I'll open the shop.
❌ Otevři okna každé ráno.
Incorrect — a daily habit needs the imperfective: otvírej.
✅ Otvírej okna každé ráno.
Open the windows every morning.
❌ Otevru ti dveře.
Incorrect — the perfective stem keeps the ř: it's otevřu, never *otevru.
✅ Otevřu ti dveře.
I'll open the door for you.
❌ Včera jsem otevřil okno.
Incorrect — the perfective past keeps -e-, never -i-: it's otevřel, not otevřil.
✅ Včera jsem otevřel okno.
Yesterday I opened the window (male speaker).
Key Takeaways
- otvírat = imperfective (process, habit, opening hours); otevřít = perfective (one completed opening).
- The two stems differ: imperfective otví- (Class V, otvírám) vs perfective otev-
- ř (Class I, otevřu).
- The ř runs through every perfective form — otevřu, otevři, otevřel — and must not be dropped.
- Perfective "present" otevřu means "I will open"; imperfective future is budu otvírat.
- Pair it with its antonym zavírat / zavřít ("to close"), which conjugates the same way.
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Start learning Czech→Related Topics
- zavírat / zavřít — to closeA2 — Side-by-side conjugation of the aspect pair zavírat (imperfective) / zavřít (perfective), the ř in the perfective stem, the accusative object, and the antonym otvírat / otevřít.
- Aspect Pairs: The Core SystemA2 — How most Czech verbs come as a two-member aspect pair — one imperfective, one perfective — and how to learn, look up, and choose between them.
- Perfective Present = Future MeaningA2 — Why conjugating a perfective verb in the present yields a future meaning.
- Class I: -e- Verbs (nést, brát)A2 — The -e- conjugation, where the present stem can look nothing like the infinitive and has to be memorised verb by verb.
- kupovat / koupit — to buyA1 — The prototypical Czech aspect pair: imperfective kupovat versus perfective koupit, conjugated side by side, with its accusative-plus-dative government.