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How to Say Sure in Spanish: Rapid Mastery with Real Usage Patterns

Native speakers pick their word based on how close they are to someone, local habits, and if they're confirming a fact or just agreeing.

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TL;DR

  • The most common ways to say "sure" in Spanish are "claro," "por supuesto," and "seguro." Each one fits a different vibe - think formality and how enthusiastic you want to sound.
  • "Claro" is your go-to for almost everything. "Por supuesto" gives extra emphasis. "Seguro" is for when you want to sound really certain.
  • In Spain, people say "vale" a lot for casual yes, but in Latin America, "claro" and "seguro" pop up more.
  • Add "que sí" or "que no" to these words for more formality or clarity in polite or business chats.
  • Native speakers pick their word based on how close they are to someone, local habits, and if they're confirming a fact or just agreeing.

Two people having a friendly conversation with one person nodding to show agreement, set against a background with subtle Spanish cultural elements.

Core Ways to Say Sure in Spanish

Spanish has a handful of ways to show agreement or certainty. Here are the top picks:

Using Claro for Agreement

Claro is the Spanish equivalent of "sure" or "of course" in everyday conversation.

Quick Phrases:

  • ¡Claro! = Sure! / Of course!
  • Claro que sí = Sure, yes
  • Sí, claro = Yes, sure

Examples:

SituationSpanishEnglish
Accepting invitation¿Vienes a la fiesta? - ¡Claro!Are you coming to the party? - Sure!
Confirming understanding¿Entiendes? - Claro.Do you understand? - Sure.
Agreeing with statementHace calor hoy. - Sí, claro.It's hot today. - Yes, for sure.
  • Formality: Works in informal and neutral settings (friends, family, workmates)
  • Tip: "Claro" literally means "clear," so it's like saying, "It's clear - yes!"

Seguro for Certainty

Seguro is for when you want to say "sure" in the sense of "I'm certain."

Typical Forms:

  • Seguro = Sure / Certain
  • Estoy seguro/segura = I'm sure (male/female)
  • ¿Seguro? = Are you sure?

Usage Table:

ExpressionMeaningExample
Seguro que síFor sure, yes¿Vendrá Juan? - Seguro que sí.
Estoy seguroI'm certainEstoy seguro de la respuesta.
No estoy seguroI'm not sureNo estoy seguro del horario.
  • Rule → Example: Use "seguro" for certainty, not just agreement.
    Example: ¿Seguro que puedes? (Are you sure you can?)

Por Supuesto and Alternatives

Por supuesto is your formal, emphatic "of course."

Formality Table:

PhraseFormalityTranslation
Por supuestoFormalOf course
Claro que síNeutralSure, yes
Sin dudaFormal/EmphaticWithout a doubt
CiertoFormal/LiteraryCertain/True
CiertamenteVery formalCertainly

Other Options:

  • Por supuesto que sí - Of course, yes (extra emphasis)

  • Sin duda - Without a doubt

  • Desde luego - Of course (formal)

  • Cómo no - Of course (informal, Latin America)

  • Rule → Example: Use "por supuesto" in business or formal situations.
    Example: ¿Puede enviar el informe? - Por supuesto.

Sí and Affirmative Combos

is just "yes," but you can jazz it up.

Combinations:

  • = Yes
  • Sí, claro = Yes, sure
  • Sí, seguro = Yes, for sure
  • Sí, por supuesto = Yes, of course
ContextResponseNote
Simple yesBasic answer
Emphatic yes¡Sí!Add excitement
Agreeing to helpClaro / Por supuestoShows willingness
Confirming certaintySeguro / Sin dudaShows confidence
  • Rule → Example: Combine "sí" with another word for stronger agreement.
    Example: Sí, por supuesto. (Yes, of course.)

  • Regional: In Latin America, "claro" often replaces "sí" in casual talk. In Spain, both are common.

When, Why, and How Native Speakers Use These Forms

Formality: Informal vs. Formal

InformalFormal
ClaroPor supuesto
Claro que síDesde luego
SeguroCiertamente
Vale (Spain)Con seguridad
BuenoSin duda

Informal:

  • Friends, family, peers
  • Texts, casual emails

Formal:

  • Business, professional emails

  • With strangers, authority figures

  • Academic or official settings

  • Rule → Example: Use "claro" with friends, "por supuesto" at work.
    Example: ¿Te ayudo? - ¡Claro! (friend) / Por supuesto. (boss)

Certainty: Expressing and Checking

Certainty:

  • Estoy seguro / segura - I'm sure
  • Estar seguro de que + clause - To be sure that
  • Con seguridad - With certainty

Checking:

  • ¿Estás seguro? - Are you sure? (informal)
  • ¿Está seguro? - Are you sure? (formal)
  • ¿De verdad? - Really?
  • ¿En serio? - Seriously?

Doubt:

  • No estoy seguro - I'm not sure
  • No sé - I don't know
  • Tal vez - Maybe
VerbMeaningRule/Example
asegurarseto make sure / ensureAsegúrate de cerrar la puerta.
asegurarto assure / secureAseguro que es cierto.
  • Rule → Example: "Asegurarse de que" uses subjunctive.
    Example: Asegúrate de que todo esté listo.

Common Idioms and Related Words

ExpressionMeaning/Use
Claro que síOf course/Sure thing
Seguro que síFor sure/Definitely
Ya lo creoYou bet
Sin duda algunaWithout a doubt
FijoFor certain (Spain)
Related WordMeaning/Use
FirmeFirm/steady (conviction)
FiableReliable/trustworthy
Seguro (noun)Insurance/safe
A salvoSafe (out of danger)
ConfiableReliable (Latin America)
  • Rule → Example: Context decides if "seguro" means "sure," "safe," or "insurance."
    Example: Tengo seguro de salud. (I have health insurance.)

Example Sentences

ScenarioSpanishEnglish
Agreeing to plans¿Vienes a la fiesta? - Claro que sí.Are you coming to the party? - Sure thing.
Helping out¿Me ayudas mañana? - Seguro.Will you help me tomorrow? - Sure.
Confirming info¿Estás seguro de la dirección?Are you sure about the address?
Confirming info (reply)Sí, estoy seguro. La tengo anotada.Yes, I'm sure. I have it written down.
Professional¿Podemos contar con su apoyo? - Por supuesto.Can we count on your support? - Certainly.
Expressing confidenceCon seguridad llegaremos a tiempo.We'll surely arrive on time.
Checking certainty¿De verdad quieres hacerlo?Do you really want to do it?
Expressing doubtNo estoy del todo segura.I'm not entirely sure.

Frequently Asked Questions

What are some informal ways to say 'sure' in Spanish?

Spanish PhraseLiteral TranslationUsage Context
¡Claro!Of course!Most common, casual
ValeOkaySpain, casual
Sí, claroYes, of courseEveryday talk
¡Por supuesto que sí!Of course yes!Extra enthusiastic
ÓraleRight on/SureMexico, very informal

Sample Exchanges:

  • ¿Quieres ir al cine? → ¡Claro!

  • ¿Podemos contar contigo? → Sí, claro.

  • Rule → Example: Use short, direct phrases with friends.
    Example: ¿Vienes? - ¡Vale! (Spain)

What is the formal way to say 'sure' as an affirmation in Spanish?

Formal ExpressionEnglish EquivalentWhen to Use
Por supuestoCertainly/Of courseBusiness, strangers
Claro que síYes, certainlyConfirming plans or attendance
CiertamenteCertainlyVery formal speech or writing
Desde luegoCertainly/IndeedProfessional settings

Professional examples:

  • ¿Podría ayudarme con esto? → Por supuesto, con gusto. (Could you help me with this? → Sure, with pleasure.)
  • ¿Puede usted asistir? → Claro que sí, estaré presente. (Can you attend? → Sure, I'll be there.)

Usage rules:

  • Use "usted" forms and these expressions in formal situations: workplace, customer service, academia, elders, or authority figures.

How is 'seguro' used to indicate certainty in Spanish?

UsageExampleContext
Adjective (masc.)Estoy seguroMale speaker
Adjective (fem.)Estoy seguraFemale speaker
PluralEstamos segurosGroup
Short response - ¿Vienes mañana? - Seguro.Informal reply
Question FormExampleNotes
To a male¿Estás seguro?Singular, masculine
To a female¿Estás segura?Singular, feminine
Plural¿Seguros?Addressing a group

Rule → Example:

  • Rule: The form of "seguro" matches gender/number when used as an adjective.

  • Example: "Estoy segura" (female), "Estamos seguros" (group).

  • When used alone as a response, "seguro" is standard for everyone.

Examples of 'I am sure' in Spanish conversation

Spanish PhraseContextCertainty Level
Estoy seguro/aStandardHigh
Estoy completamente seguro/aEmphaticAbsolute
Estoy bastante seguro/aQualifiedModerate
No estoy seguro/aDoubtLow

Sample conversations:

  • Estoy seguro de que vendrá. (I am sure he will come.)
  • ¿Segura? → Sí, completamente segura. (Sure? → Yes, completely sure.)
  • Estoy seguro de la respuesta. (I am sure of the answer.)
  • No estoy muy segura de eso. (I'm not very sure about that.)

Rule → Example:

  • Rule: The adjective agrees with the speaker’s gender and can be modified for emphasis.
  • Example: "Estoy completamente seguro," "Estoy bastante segura."

Expressions equivalent to 'for sure' in Spanish

ExpressionStrengthNotes
SeguroDirectMost common
De seguroEmphaticAdds emphasis
Por seguroRegionalLess common
Sin dudaStrong"Without a doubt"
DefinitivamenteStrong"Definitely"

Sentence examples:

  • Vendrá seguro. (He'll come for sure.)
  • Seguro que llueve mañana. (For sure it will rain tomorrow.)
  • Sin duda es la mejor opción. (For sure it's the best option.)
RegionCommon ExpressionUsage
MexicoSeguroStandard
SpainSeguro, Fijo"Fijo" is casual
ArgentinaSeguro, Re seguro"Re" adds intensity

Rule → Example:

  • Rule: "Seguro" can appear at the start, middle, or end of a sentence.
  • Example: "Seguro que viene," "Viene seguro," "Seguro viene."