GPT-4o mini TTSvsMAI-Voice-2.1

Compare

Speed and accuracy

Left is faster. Higher reads more hard parts right.

Fast and accurate60%70%80%90%100%00.5s1s1.5s2sTime until the caller hears the voice
  • GPT-4o mini TTS688 ms · 82.7%
  • MAI-Voice-2.1861 ms · 82.2%

GPT-4o mini TTS is better on non-streaming latency, accuracy and naturalness. MAI-Voice-2.1 is better on price.

Last updated Methodology by Dileep Chagam

Which is better at what

Measure by measure, the same sentences, the same place.

MeasureGPT-4o mini TTSMAI-Voice-2.1
  • Non-streaming latency (median)GPT-4o mini TTS is better688 ms861 ms
  • Streaming latency (median)Can't streamCan't stream
  • Extra audio after a stopNo stop messageNo stop message
  • Hard parts read rightGPT-4o mini TTS is better82.7%82.2%
  • Naturalness (1 to 5)GPT-4o mini TTS is better4.434.18
  • Price per 1M charactersMAI-Voice-2.1 is better$25.70$22.00
Hard parts read rightGPT-4o mini TTSMAI-Voice-2.1
  • Numbers and shorthand7 a.m. · 20% · 36°F · approx.78%85%
  • Codes and addressesSAVE20 · help@north-clinic.org · 1-800-555-019978%67%
  • Read from contextSt. Mary's on Main St. · Dr. Okafor96%73%
  • Medical termslevothyroxine · gastroenterology94%99%

An estimate: speech-to-text transcribers scored it, not people.

Hear both

The same sentence, read by each voice.

19 sentences, the same for both
  1. 01A greetingThanks for calling Cedar Valley Family Practice, this is Riley. How can I help you today?
  2. 02MoneyYour current balance is $1,347.09.
  3. 03A dateThe order was placed on 2026-03-14 and shipped two days later.
  4. 04Tracking codeThe tracking number is 1Z 7A4 X29 0341 8867.
  5. 05Email addressI have m.rivera88@example.org, is that still current?
  6. 06An Irish nameSiobhan Ó Briain called about the invoice.

How each ranks among all 26

MeasureGPT-4o mini TTSMAI-Voice-2.1
  • Non-streaming latency (median)21 of 2623 of 26
  • Streaming latency (median)n/an/a
  • Extra audio after a stopn/an/a
  • Hard parts read right12 of 2613 of 26
  • Naturalness (1 to 5)7 of 2624 of 26
  • Price per 1M characters11 of 259 of 25

GPT-4o mini TTS vs MAI-Voice-2.1 FAQ

  • GPT-4o mini TTS. GPT-4o mini TTS: 688 ms. MAI-Voice-2.1: 861 ms.

  • Neither has a figure. GPT-4o mini TTS: Can't stream. MAI-Voice-2.1: Can't stream.

  • Neither has a figure. GPT-4o mini TTS: No stop message. MAI-Voice-2.1: No stop message.

  • GPT-4o mini TTS. GPT-4o mini TTS: 82.7%. MAI-Voice-2.1: 82.2%.

  • MAI-Voice-2.1. GPT-4o mini TTS: $25.70. MAI-Voice-2.1: $22.00.