CekuraBench

Cartesia Sonic 3.6vsCartesia Sonic 3.5

Cartesia Sonic 3.6Cartesia Sonic 3.5
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
  • Cartesia Sonic 3.6286 ms · 74.9%
  • Cartesia Sonic 3.5261 ms · 73.1%

Cartesia Sonic 3.6 is better on stopping and accuracy. Cartesia Sonic 3.5 is better on non-streaming latency and streaming latency.

Last updated Methodology by Dileep Chagam

Which is better at what

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

MeasureCartesia Sonic 3.6Cartesia Sonic 3.5
  • Non-streaming latency (median)Cartesia Sonic 3.5 is better286 ms261 ms
  • Streaming latency (median)Cartesia Sonic 3.5 is better270 ms244 ms
  • Extra audio after a stopCartesia Sonic 3.6 is better764 ms809 ms
  • Hard parts read rightCartesia Sonic 3.6 is better74.9%73.1%
  • Naturalness (1 to 5)Level4.414.41
  • Price per 1M charactersLevel$39.20$39.20
Hard parts read rightCartesia Sonic 3.6Cartesia Sonic 3.5
  • Numbers and shorthand7 a.m. · 20% · 36°F · approx.71%69%
  • Codes and addressesSAVE20 · help@north-clinic.org · 1-800-555-019975%75%
  • Read from contextSt. Mary's on Main St. · Dr. Okafor58%54%
  • Medical termslevothyroxine · gastroenterology100%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

MeasureCartesia Sonic 3.6Cartesia Sonic 3.5
  • Non-streaming latency (median)11 of 268 of 26
  • Streaming latency (median)12 of 1810 of 18
  • Extra audio after a stop5 of 66 of 6
  • Hard parts read right23 of 2624 of 26
  • Naturalness (1 to 5)12 of 2614 of 26
  • Price per 1M characters16 of 2516 of 25

Related comparisons

Cartesia Sonic 3.6 vs Cartesia Sonic 3.5 FAQ

  • Cartesia Sonic 3.5. Cartesia Sonic 3.6: 286 ms. Cartesia Sonic 3.5: 261 ms.

  • Cartesia Sonic 3.5. Cartesia Sonic 3.6: 270 ms. Cartesia Sonic 3.5: 244 ms.

  • Cartesia Sonic 3.6. Cartesia Sonic 3.6: 764 ms. Cartesia Sonic 3.5: 809 ms.

  • Cartesia Sonic 3.6. Cartesia Sonic 3.6: 74.9%. Cartesia Sonic 3.5: 73.1%.

  • They are level. Cartesia Sonic 3.6: $39.20. Cartesia Sonic 3.5: $39.20.