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NIST 2021 Speaker Recognition Evaluation (SRE21)

The 2021 Speaker Recognition Evaluation (SRE21) is the next in an ongoing series of speaker recognition evaluations conducted by the US National Institute of Standards and Technology (NIST) since 1996. The objectives of the evaluation series are (1) to effectively measure system-calibrated performance of the current state of technology, (2) to provide a common framework that enables the research community to explore promising new ideas in speaker recognition, and (3) to support the community in their development of advanced technology incorporating these ideas. The evaluations are intended to be of interest to all researchers working on the general problem of text-independent speaker recognition. To this end, the evaluations are designed to focus on core technology issues and to be simple and accessible to those wishing to participate.

SRE21 will be organized similar to SRE19, focusing on speaker detection over conversational telephone speech (CTS) and audio from video (AfV). It will introduce the following new features, thanks to a new multimodal and multilingual (i.e., with multilingual subjects) corpus collected outside North America:

  •  trials (target and non-target) with enrollment and test segments originating from different source types (i.e., CTS and AfV)
  • trials (target and non-target) with enrollment and test segments spoken in different languages (i.e., cross-lingual trials)

Similar to SRE19, in addition to the audio-only track, SRE21 will feature a visual-only track and an audio-visual track involving automatic person detection using audio, image, and video material. System submission is required for the audio and audio-visual tracks, and optional for the visual track.

Note that in order to participate in SRE21, a team must first make a valid submission to the CTS Challenge (

Participation in the SRE21 is open to all who find the evaluation of interest and are able to comply with the evaluation rules set forth in the evaluation plan. Although there is no cost to participate in SRE21 (i.e., the evaluation data, web platform, and scoring software will be available free of charge), participating teams must be represented at the post-evaluation workshop to be organized in December 2021.

Send questions to sre_poc [at] (sre_poc[at]nist[dot]gov)

Evaluation Plan

SRE21 Evaluation Plan

Registration Website


Created July 12, 2021