F vs V

proof vs prove: hear and say the difference

proof and prove are identical except for one sound: proof has the f sound, /f/, and prove has the v sound, /v/. The mouth is identical — top teeth on the bottom lip — and only the voice changes: put a hand on your throat and V buzzes while F is silent.

Listen

The two words

proof

/pruːf/

the f sound

prove

/pruːv/

the v sound
Articulation

The difference

What actually changes

The mouth is identical — top teeth on the bottom lip — and only the voice changes: put a hand on your throat and V buzzes while F is silent.

proof — /f/

In the mouth
Lips
Bottom lip drawn up lightly under the top teeth.
Tongue
Free and low — it does nothing.
Jaw
Nearly closed.
Tongue and lips

prove — /v/

In the mouth
Lips
Bottom lip under the top teeth — the same contact as F.
Tongue
Low and uninvolved.
Jaw
Nearly closed.
Tongue and lips
In context

Each word in a sentence

  • proof

    There is no proof of that.

  • prove

    You will have to prove it.

Who merges this

Why this pair is hard

Hindi, Urdu, Punjabi, Gujarati and Telugu merge v with w, so V drifts away from the teeth. Bengali, Japanese, Korean and Mandarin have no v and substitute b or w. Arabic has no v and uses f, which collapses the pair entirely. German devoices a final consonant, so 'leave' can end like 'leaf'.

Questions

Straight answers

What is the difference between "proof" and "prove"?

One sound. proof is /pruːf/ and prove is /pruːv/ — everything else in the two words is identical, so that single contrast carries the whole meaning. The mouth is identical — top teeth on the bottom lip — and only the voice changes: put a hand on your throat and V buzzes while F is silent.

Why do I say "proof" and "prove" the same way?

Hindi, Urdu, Punjabi, Gujarati and Telugu merge v with w, so V drifts away from the teeth. Bengali, Japanese, Korean and Mandarin have no v and substitute b or w. Arabic has no v and uses f, which collapses the pair entirely. German devoices a final consonant, so 'leave' can end like 'leaf'.

Should I train my ear or my mouth first?

Your ear. If you cannot reliably hear which word was said, your mouth has no target to aim at, and drilling produces a sound you cannot check. Run the listening test on this page until you are scoring four or five out of five, then record the pair.

Practise this word

Say "proof" and "prove" and see which one you said

One take covers both words: reference mode aligns each sound against its target, so the contrast comes back scored on both sides. Free, private, in your browser.