Synonyms of authenticate

authenticate

verb

ə-ˈthen-ti-ˌkāt 

1

as in to certify

to declare (something) to be true or genuine

a jeweler authenticated the diamond as real

Synonyms & Similar Words

• certify
• guarantee
• affirm
• attest
• testify (to)
• witness
• assert
• vouch (for)
• avouch
• warrant
• aver
• profess
• vow
• avow

2

as in to verify

to give evidence or testimony to the truth or factualness of

we require more than simply your word to authenticate this story

Synonyms & Similar Words

• verify
• confirm
• argue
• validate
• support
• certify
• corroborate
• prove
• vindicate
• attest
• bear out
• substantiate
• demonstrate
• witness
• establish
• affirm
• testify (to)
• reinforce
• assert
• document
• guarantee
• vouch (for)
• declare
• back (up)
• warrant
• profess
• aver
• avouch
• avow

Antonyms & Near Antonyms

• disprove
• refute
• rebut
• deny
• contradict
• challenge
• gainsay
• question
• dispute
• disavow
• contest
• disclaim

Synonym Chooser

How does the verb authenticate contrast with its synonyms?

Some common synonyms of authenticate are confirm, corroborate, substantiate, validate, and verify. While all these words mean "to attest to the truth or validity of something," authenticate implies establishing genuineness by adducing legal or official documents or expert opinion.

handwriting experts authenticated the diaries

When might confirm be a better fit than authenticate?

While the synonyms confirm and authenticate are close in meaning, confirm implies the removing of doubts by an authoritative statement or indisputable fact.

confirmed the reports

Where would corroborate be a reasonable alternative to authenticate?

The words corroborate and authenticate are synonyms, but do differ in nuance. Specifically, corroborate suggests the strengthening of what is already partly established.

witnesses corroborated his story

In what contexts can substantiate take the place of authenticate?

The words substantiate and authenticate can be used in similar contexts, but substantiate implies the offering of evidence that sustains the contention.

the claims have yet to be substantiated

When is it sensible to use validate instead of authenticate?

While in some cases nearly identical to authenticate, validate implies establishing validity by authoritative affirmation or by factual proof.

validated the hypothesis by experiments

When can verify be used instead of authenticate?

Although the words verify and authenticate have much in common, verify implies the establishing of correspondence of actual facts or details with those proposed or guessed at.

all statements of fact in the article have been verified

Example Sentences

Recent Examples of authenticate

For instance, commission hearings don’t include the right to testify under oath, authenticate evidence or subpoena and cross-examine witnesses, Talcott said. —Calmatters, Mercury News, 15 Jan. 2026

For instance, commission hearings don’t include the right to testify under oath, authenticate evidence or subpoena and cross-examine witnesses, Talcott said. —Calmatters, Oc Register, 14 Jan. 2026

Her lawyers hired an expert at Johns Hopkins University to authenticate her documents. —Mike Hellgren, CBS News, 8 Jan. 2026

But while that’s a compelling story, the researchers failed to authenticate the age of the DNA, a significant limitation of the study, Caramelli says. —Jackie Flynn Mogensen, Scientific American, 7 Jan. 2026