Synonyms of certainty

certainty

noun

ˈsər-tᵊn-tē 

1

as in assurance

a state of mind in which one is free from doubt

I have full certainty that I'll pass the test

Synonyms & Similar Words

• assurance
• confidence
• satisfaction
• conviction
• certitude
• assuredness
• sureness
• surety
• positiveness
• cocksureness
• doubtlessness
• determination
• face
• dogmatism
• authoritarianism
• resolution
• decisiveness
• firmness
• resolve
• purposefulness
• resoluteness

Antonyms & Near Antonyms

• uncertainty
• doubt
• hesitation
• hesitancy
• irresolution
• concern
• disbelief
• incertitude
• indecisiveness
• incredulity
• anxiety
• unbelief
• nonconfidence
• suspicion
• distrust
• misgiving
• mistrust

2

as in likelihood

the quality or state of being impossible to avoid or evade

the proverbial certainty of death and taxes

Synonyms & Similar Words

• likelihood
• inevitability
• probability
• inevitableness
• ineluctability
• inexorability
• relentlessness
• inexorableness

Antonyms & Near Antonyms

• uncertainty
• improbability
• unlikelihood
• preventability
• doubtfulness
• unlikeliness
• dubiousness

Synonym Chooser

How does the noun certainty differ from other similar words?

The words certitude and conviction are common synonyms of certainty. While all three words mean "a state of being free from doubt," certainty and certitude are very close; certainty may stress the existence of objective proof.

claims that cannot be confirmed with scientific certainty

When might certitude be a better fit than certainty?

The synonyms certitude and certainty are sometimes interchangeable, but certitude may emphasize a faith in something not needing or not capable of proof.

believes with certitude in an afterlife

When is conviction a more appropriate choice than certainty?

In some situations, the words conviction and certainty are roughly equivalent. However, conviction applies especially to belief strongly held by an individual.

holds firm convictions on every issue

Example Sentences

Recent Examples of certainty

Nobody can say with any real certainty who is right or wrong, but based on gut feeling alone, the Internet has already drawn lines. — Air Mail, 17 Oct. 2026

There’s a learning curve, sure, where succeeding at one thing gives you an idea to try something else and have some certainty about how well the AI agent will handle the task. — Adam Clark Estes, Vox, 16 Oct. 2026

But, as Greene Epstein pointed out, perhaps one of the only certainties that theater artists have is in the fact that AI can’t show up in real time and space (like the Westside location) to, well, act. — Laura Zornosa, Los Angeles Times, 16 Oct. 2026

As the near-certainty of a record-breaking super El Niño has become clear, the scientists who predict and study it have been inundated by inquiries from the press and public. — Andrew Freedman, CNN Money, 14 Oct. 2026