Dudar Conjugation in Spanish
Introduction
dudar means "to doubt" in English, and it is one of the verbs you will meet constantly in everyday Spanish — for expressing doubt about a fact or a statement. Learning it properly means more than memorising one form: the verb changes across thirteen tenses, and this page gives you every one of them, with the exact forms from the VerbFlow engine, so you can check any person or tense in seconds. Dudar is a regular -ar verb verb, and it is regular in every tense. That matters because the patterns on this page are the patterns you will reuse every time you speak or write. Work through the tables first, then read the notes under each tense — they explain when to use each tense and what to watch out for with this verb in particular. A natural example is: Cada día, yo dudo de su historia. — "Every day, I doubt his story." Once you can say that sentence confidently, try changing the person and the tense using the tables below.
Quick facts
| Infinitive | dudar |
| Translation | to doubt |
| Verb type | Regular -ar verb |
| Gerund | dudando |
| Past participle | dudado |
| Auxiliary | haber (all compound tenses) |
| Irregular tenses | regular in every tense |
Full conjugation of dudar
Present indicative
| Person | Form |
|---|---|
| yo | dudo |
| tú | dudas |
| él / ella / Ud. | duda |
| nosotros / nosotras | dudamos |
| vosotros / vosotras | dudáis |
| ellos / ellas / Uds. | dudan |
Preterite
| Person | Form |
|---|---|
| yo | dudé |
| tú | dudaste |
| él / ella / Ud. | dudó |
| nosotros / nosotras | dudamos |
| vosotros / vosotras | dudasteis |
| ellos / ellas / Uds. | dudaron |
Imperfect
| Person | Form |
|---|---|
| yo | dudaba |
| tú | dudabas |
| él / ella / Ud. | dudaba |
| nosotros / nosotras | dudábamos |
| vosotros / vosotras | dudabais |
| ellos / ellas / Uds. | dudaban |
Future
| Person | Form |
|---|---|
| yo | dudaré |
| tú | dudarás |
| él / ella / Ud. | dudará |
| nosotros / nosotras | dudaremos |
| vosotros / vosotras | dudaréis |
| ellos / ellas / Uds. | dudarán |
Conditional
| Person | Form |
|---|---|
| yo | dudaría |
| tú | dudarías |
| él / ella / Ud. | dudaría |
| nosotros / nosotras | dudaríamos |
| vosotros / vosotras | dudaríais |
| ellos / ellas / Uds. | dudarían |
Present subjunctive
| Person | Form |
|---|---|
| yo | dude |
| tú | dudes |
| él / ella / Ud. | dude |
| nosotros / nosotras | dudemos |
| vosotros / vosotras | dudéis |
| ellos / ellas / Uds. | duden |
Imperfect subjunctive (-ra forms)
| Person | Form |
|---|---|
| yo | dudara |
| tú | dudaras |
| él / ella / Ud. | dudara |
| nosotros / nosotras | dudáramos |
| vosotros / vosotras | dudarais |
| ellos / ellas / Uds. | dudaran |
Present perfect
| Person | Form |
|---|---|
| yo | he dudado |
| tú | has dudado |
| él / ella / Ud. | ha dudado |
| nosotros / nosotras | hemos dudado |
| vosotros / vosotras | habéis dudado |
| ellos / ellas / Uds. | han dudado |
Pluperfect
| Person | Form |
|---|---|
| yo | había dudado |
| tú | habías dudado |
| él / ella / Ud. | había dudado |
| nosotros / nosotras | habíamos dudado |
| vosotros / vosotras | habíais dudado |
| ellos / ellas / Uds. | habían dudado |
Future perfect
| Person | Form |
|---|---|
| yo | habré dudado |
| tú | habrás dudado |
| él / ella / Ud. | habrá dudado |
| nosotros / nosotras | habremos dudado |
| vosotros / vosotras | habréis dudado |
| ellos / ellas / Uds. | habrán dudado |
Conditional perfect
| Person | Form |
|---|---|
| yo | habría dudado |
| tú | habrías dudado |
| él / ella / Ud. | habría dudado |
| nosotros / nosotras | habríamos dudado |
| vosotros / vosotras | habríais dudado |
| ellos / ellas / Uds. | habrían dudado |
Imperative — affirmative
| Person | Form |
|---|---|
| tú | duda |
| él / ella / Ud. | dude |
| nosotros / nosotras | dudemos |
| vosotros / vosotras | dudad |
| ellos / ellas / Uds. | duden |
Imperative — negative
| Person | Form |
|---|---|
| tú | dudes |
| él / ella / Ud. | dude |
| nosotros / nosotras | dudemos |
| vosotros / vosotras | dudéis |
| ellos / ellas / Uds. | duden |
Gerund: dudando · Past participle: dudado
Dudar in every tense — notes and examples
Present indicative
The present is the tense for habits, facts and what is happening now. It is the first tense to master, because the present subjunctive and the affirmative imperative are both built from the present yo form. Example: Cada día, yo dudo de su historia. — "Every day, I doubt his story."
Preterite
The preterite is for completed actions in the past — things that started and finished at a definite moment. Use it for a single event, a sequence of events, or an action with a clear end. Example: Ayer, yo dudé de su historia. — "Yesterday, I doubted his story."
Imperfect
The imperfect is for the past without a definite end: habits, background scenes, descriptions and actions in progress when something else happened. It never states when the action finished. Example: Antes, yo dudaba de su historia. — "Before, I doubted his story."
Future
The future is for what will happen, and also for guesses about the present ("I wonder if…"). For regular verbs it is the infinitive plus the endings -é, -ás, -á, -emos, -éis, -án. Example: Mañana, yo dudaré de su historia. — "Tomorrow, I will doubt his story."
Conditional
The conditional is for what would happen — polite requests, hypothetical results and reported expectations. It shares its stem with the future, so any irregular future stem appears here too. Example: Yo dudaría de su historia si tuviera la oportunidad. — "I would doubt his story if I had the chance."
Present subjunctive
The present subjunctive is for wishes, doubts, emotions and other non-facts after que, and after expressions such as ojalá, es importante que or no creo que. It is not a tense for stating facts. Example: Espero que ella dude de su historia. — "I hope she will doubt his story."
Imperfect subjunctive (-ra forms)
The imperfect subjunctive (-ra forms) is for wishes and doubts about the past, and for the if-part of hypothetical sentences (si + imperfect subjunctive, conditional). This page shows the -ra forms from the engine. Example: Si ella dudara de su historia, todo cambiaría. — "If she doubted his story, everything would change."
Present perfect
The present perfect (haber + past participle) is for past actions connected to the present — recent events, experience, or something that has just happened. The auxiliary is always haber. Example: Yo he dudado que llegue a tiempo varias veces. — "I have doubted that he will arrive on time several times."
Pluperfect
The pluperfect (había + past participle) is the past of the past: something that had already happened before another past event. Example: Yo había dudado de su historia antes de la reunión. — "I had doubted his story before the meeting."
Future perfect
The future perfect (habré + past participle) is for something that will already be finished by a future moment, or for a guess about the past. It is less common in speech than the simple future. Example: Para mañana, yo habré dudado de su historia. — "By tomorrow, I will have doubted his story."
Conditional perfect
The conditional perfect (habría + past participle) is for what would have happened — the past of the conditional, used for regrets and unreal past conditions. Example: Yo habría dudado de su historia si hubiera tenido tiempo. — "I would have doubted his story if I had had time."
Imperative — affirmative
The affirmative imperative is for direct orders, instructions and invitations. The tú form comes from the present él/ella form, and the formal, nosotros and plural forms come from the present subjunctive. Example: ¡duda de su historia! — "Doubt his story!"
Imperative — negative
The negative imperative (no + subjunctive) is for telling someone not to do something. All five persons come from the present subjunctive, which is why they look different from the affirmative tú form. Example: No dudes de su historia. — "Do not doubt his story."
Example sentences with dudar
Yo dudo de su historia. — "I doubt his story."
¿Tú dudas que llegue a tiempo? — "Do you doubt that he will arrive on time?"
Ayer, él dudó de su historia. — "Yesterday, he doubted his story."
Nosotros dudamos que llegue a tiempo a tiempo. — "We doubted that he will arrive on time on time."
Antes, ellos dudaban de su historia. — "Before, they doubted his story."
Mañana, yo dudaré que llegue a tiempo. — "Tomorrow, I will doubt that he will arrive on time."
Nosotros dudaríamos de su historia si pudiéramos. — "We would doubt his story if we could."
Yo he dudado que llegue a tiempo varias veces. — "I have doubted that he will arrive on time several times."
Espero que ella dude de su historia. — "I hope she will doubt his story."
Ahora mismo, yo estoy dudando que llegue a tiempo. — "Right now, I am doubting that he will arrive on time."
Common mistakes with dudar
1. Dropping the accent on the preterite yo form
The preterite yo form is dudé — with the accent. Without it the word is misspelled, and in some verbs the accent is the only thing separating one tense from another.
2. Confusing dudar with creer (to believe)
dudar means "to doubt", while creer means "to believe". They overlap in English but they are not interchangeable in Spanish: use dudar when you mean expressing doubt about a fact or a statement, and creer for its own meaning. Check the conjugation of creer before choosing.
3. Mixing up the preterite and the imperfect
Ayer yo dudé de su historia (preterite: one finished event yesterday) is not the same as antes yo dudaba de su historia (imperfect: what used to happen). If you can add "yesterday" or "last week", you usually want the preterite; if you can add "used to", you want the imperfect.
4. Using the indicative after dudar + que
After dudar, the subordinate clause takes the subjunctive: dudar que ella dude de su historia. The indicative (duda) is wrong here, because dudar expresses a wish or a doubt, not a stated fact.
5. Using estar instead of haber in the perfect tenses
The present perfect is he dudado (haber + participle), never estoy dudado. Haber is the only auxiliary for compound tenses in Spanish.
Quiz: dudar
1. Yo ___ de su historia.
a. duda b. dudo c. dudan
2. Ella ___ de su historia.
a. dudo b. duda c. dudan
3. Ayer, yo ___ de su historia.
a. dudo b. dudé c. duda
4. Ellos ___ de su historia ayer.
a. dudo b. dudaron c. duda
5. Antes, yo ___ de su historia.
a. dudo b. dudaba c. duda
6. Mañana, yo ___ de su historia.
a. dudo b. dudaré c. duda
7. Yo ___ de su historia si pudiera.
a. dudo b. dudaría c. duda
8. Espero que ella ___ de su historia.
a. dudo b. dude c. duda
9. Ahora mismo, yo estoy ___ que llegue a tiempo.
a. dudado b. dudando c. dudo
10. Yo he ___ que llegue a tiempo varias veces.
a. dudando b. dudado c. dudo
Answer key
dudo — present tense, yo form.
duda — present tense, él/ella form.
dudé — preterite, yo form — a finished action yesterday.
dudaron — preterite, ellos/ellas form.
dudaba — imperfect, yo form — a past habit.
dudaré — future, yo form.
dudaría — conditional, yo form — a hypothetical.
dude — present subjunctive after 'espero que'.
dudando — gerund — the progressive is estar + gerund.
dudado — past participle — the present perfect is haber + participle.
Frequently asked questions about dudar
What does dudar mean in English?
Dudar means "to doubt". It is used for expressing doubt about a fact or a statement. A simple example is yo dudo de su historia — "I doubt his story."
Is dudar regular or irregular?
Dudar is a regular -ar verb verb, and it is regular in every tense. The forms that most often catch learners out are the present yo form dudo, the preterite yo form dudé and the past participle dudado — learn those three first, then fill in the rest from the tables above.
What is the gerund and the past participle of dudar?
The gerund is dudando (used for the progressive: estoy dudando) and the past participle is dudado (used with haber in all perfect tenses: he dudado). Both forms are used constantly, so they are worth memorising on their own.
How do I say "I doubt" in the past?
It depends on the meaning. For one finished action use the preterite: ayer yo dudé de su historia — "yesterday I doubted his story". For a past habit or background use the imperfect: antes yo dudaba de su historia — "before, I doubted his story". The mistake most learners make is using one for the other.
Does dudar take the subjunctive?
Yes, often. After dudar, a subordinate clause with que usually takes the subjunctive, because dudar expresses a wish or a doubt rather than a fact: dudar que ella dude de su historia. If you use the indicative there, the sentence sounds wrong to a native speaker.