Fact · Languages and accents

In a 2024 analysis of OpenAI's Whisper speech model, the authors found better performance on North American English accents than on British and Irish English accents.

Checked against its source on October 17, 2026

In the source's own words

“The findings indicate better performance on North American vs British and Irish English accents”

Evaluating OpenAI's Whisper ASR: Performance analysis across diverse accents and speaker traits, Calbert Graham and Nathan Roll, Cambridge Open Engage (preprint); published in JASA Express Letters, 2024, 2024, Abstract.

What it measures: The authors tested Whisper on native and non-native English accents and linked error rates to speaker traits such as sex, first-language type and second-language proficiency. The abstract gives the direction of the result, not the size of the gap.
What it does not show: Whisper is an open model, not the engine inside Apple's or Microsoft's dictation. North American, British and Irish are broad groups, and the abstract does not give the figures for each group.