The short answer
Much less than you would think. The engine is trained on speech from all over the world. Speak at your normal pace, and use the dictionary for any word it keeps missing.
Why accents matter less than they used to
Older dictation software was trained on a narrow range of voices and needed a long training session before it understood yours. Modern speech engines learn from a huge range of speakers, in many countries and many accents. A Scottish, Irish, Indian, Nigerian, Australian, Thai or Spanish accent in English is normal speech to them, with no training session.
Speak normally, not slowly
The most common mistake is slowing down and pronouncing every word carefully. It feels helpful, but it makes speech less like what the engine has learned from. You will get better results at your normal speaking pace, in full sentences, as if you were talking to a colleague.
Where accents can still trip it up
- Names and rare words, which have no common pronunciation to fall back on. Add them to your dictionary once.
- Words that sound like other words in your accent. Add the word with what it is heard as: "thirty (heard as dirty)".
- Very short clips of one or two words, where there is little context. Say the whole sentence.
Speaking English as a second language
Many people dictate in English as their second or third language. Two things help:
- Tick both your languages in Settings, so a short clip is never mistaken for the wrong one.
- Let the clean-up do the grammar. It tidies sentences into natural English while keeping your meaning. If you would rather it changed less, use the Clean style.
You can also speak in your own language and have it written in English with the Translate style. See Can it translate as I speak?
Related questions
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