CekuraBench

Inworld TTS-2 FlashvsSoniox TTS RT v2

Inworld TTS-2 FlashSoniox TTS RT v2
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
  • Inworld TTS-2 Flash46 ms · 93.2%
  • Soniox TTS RT v2241 ms · 83.6%

Inworld TTS-2 Flash is better on non-streaming latency, streaming latency, accuracy and naturalness. Soniox TTS RT v2 is better on stopping and price.

Last updated Methodology by Dileep Chagam

Which is better at what

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

MeasureInworld TTS-2 FlashSoniox TTS RT v2
  • Non-streaming latency (median)Inworld TTS-2 Flash is better46 ms241 ms
  • Streaming latency (median)Inworld TTS-2 Flash is better45 ms183 ms
  • Extra audio after a stopSoniox TTS RT v2 is betterNo stop message0 ms
  • Hard parts read rightInworld TTS-2 Flash is better93.2%83.6%
  • Naturalness (1 to 5)Inworld TTS-2 Flash is better4.464.37
  • Price per 1M charactersSoniox TTS RT v2 is better$15.00$14.81
Hard parts read rightInworld TTS-2 FlashSoniox TTS RT v2
  • Numbers and shorthand7 a.m. · 20% · 36°F · approx.93%78%
  • Codes and addressesSAVE20 · help@north-clinic.org · 1-800-555-019986%86%
  • Read from contextSt. Mary's on Main St. · Dr. Okafor98%88%
  • Medical termslevothyroxine · gastroenterology99%97%

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

MeasureInworld TTS-2 FlashSoniox TTS RT v2
  • Non-streaming latency (median)1 of 267 of 26
  • Streaming latency (median)2 of 189 of 18
  • Extra audio after a stopn/a1 of 6
  • Hard parts read right2 of 2611 of 26
  • Naturalness (1 to 5)5 of 2617 of 26
  • Price per 1M characters2 of 251 of 25

Related comparisons

Inworld TTS-2 Flash vs Soniox TTS RT v2 FAQ

  • Inworld TTS-2 Flash. Inworld TTS-2 Flash: 46 ms. Soniox TTS RT v2: 241 ms.

  • Inworld TTS-2 Flash. Inworld TTS-2 Flash: 45 ms. Soniox TTS RT v2: 183 ms.

  • Soniox TTS RT v2. Inworld TTS-2 Flash: No stop message. Soniox TTS RT v2: 0 ms.

  • Inworld TTS-2 Flash. Inworld TTS-2 Flash: 93.2%. Soniox TTS RT v2: 83.6%.

  • Soniox TTS RT v2. Inworld TTS-2 Flash: $15.00. Soniox TTS RT v2: $14.81.