Speaker identification

Speaker identification that works across every file in your project

A unique voice fingerprint is extracted from each interview and matched across the whole project. Rename a speaker once and the new label propagates everywhere they appear. Watch the demo below colour two speakers in real time as a clip plays.

Try it now

A working sandbox. No sign-up, no project. Sample data only.

  • Voice fingerprinting runs on our servers. No raw audio is sent to a third-party service.
  • Cross-file matching: name a speaker on Day 04 and Day 17 picks up the label too.
  • Merge, split or rename identities project-wide. Renames apply everywhere instantly.
  • Correct a turn and the nearby matches are reconsidered.
  • Too few speakers found? Re-diarize listens to the audio again and keeps every word, edit and note.
  • A change history: every naming, merge and reset, who did it, across how many files.
VOICE-PRINT MATCHING
demo
IN
INTERVIEWER

Tell me about the night the override failed.

How it works

Three steps from raw material to result.

STEP 01
Speaker turn
00:04:31 to 00:04:48 · 17s
Voice fingerprint created
Analysed on server · not shared
Voice fingerprints captured

Each speaker turn is analysed locally on our server to create a unique voice fingerprint. No audio is sent to a third-party speaker service.

STEP 02
Cross-file matches
MATCHDay 04 · Marin Interview
MATCHDay 09 · Marin Followup
REVIEWDay 17 · Ensemble
Matched across the project

Fingerprints are compared against existing project identities. Strong matches auto-group; ambiguous ones surface for review.

STEP 03
Rename once
EM
14 files updated instantly
Including files from 3 weeks ago
One name everywhere

Rename a speaker on any file and the change ripples to every appearance, including files you uploaded weeks ago.

Listen again

When a file comes back with too few speakers, re-diarize relabels the lines in place. The words and everything built on them stay.

RE-DIARIZE
demo
Only 1 speaker found in a 42-minute file.
00:12:04SPEAKER 1
So you were the one who signed the order?
00:12:09SPEAKER 1
I signed what I was given. That is not the same thing.
00:12:16SPEAKER 1
He is right about that, you know.
The audio is listened to again and the lines are relabelled in place. Edits, notes and paper cut rows built on the transcript stay where they are.

Frequently asked questions

How does cross-file matching work?

Each speaker turn is analysed to create a unique voice fingerprint, then compared against the identities already in the project. Matches above a tuned confidence threshold are grouped automatically; ambiguous ones are flagged for manual review.

Can I merge two speakers I named separately?

Yes. Merge from the speaker panel and all appearances of the absorbed identity are renamed across every file. Splitting one identity into two is also supported.

What if the system gets a speaker wrong?

Correct the label on any turn and the system re-analyses and reconsiders nearby matches automatically. A project-wide cleanup pass can be triggered manually after large edits.

Does it work for two speakers who sound alike?

Voice fingerprinting separates most adult voices reliably even when timbre is close. Identical-twin-level similarity occasionally needs manual review, especially in short turns under two seconds.

Is speaker identification run locally?

No. It runs on our servers, not in your browser. No raw audio is sent to a third-party speaker service.

The file came back with one speaker and the room had four. What do I do?

Use Re-diarize on the file. It listens to the audio again with the newest speaker model and keeps your transcript text. A file over ten minutes with one voice throughout gets a warning with the button on it. The optional Expected speakers box is an upper limit that guides the model when it is unsure, and the limit from the first run is not carried over.

What is the difference between Re-diarize and Reset speakers?

Reset speakers rewinds every line to the labels the provider first gave, which can never produce more speakers than the first run found. Re-diarize listens again and can. After a Re-diarize, Reset rewinds to the new split.

Can I tell the same person apart in two places?

Yes. Give the speaker a one-letter location tag in each folder, such as L for London and B for Berkeley. The speaker stays one identity and every name-based feature still treats them as one person. The tag shows as a second, coloured half of the chip in the paper cut, Tara MacAulay | L, and is written in brackets in exports, Tara MacAulay (L). Most speakers will never need one.

Related capabilities

Further reading

Background guides and comparisons.

Put speaker identification to work on your project.

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