Cartesia vs Deepgram
Cartesia holds a tighter latency spread than either Deepgram model.
Callers hear the slow turns, not the average.
Latency consistency
Sonic 3.5's slowest calls stay close to its fastest
- An average hides the calls that break a conversation. The spread is what a caller actually hears.
- Sonic 3.5's slowest measured call stays under half a second. Both Deepgram models run past that.
Latency Variation: Distribution of TTFA values
Lower is better
Tail latency
Cartesia stays ahead where it counts most
- P95 is the turn that one caller in twenty gets, so it sets how often a conversation stalls.
- Sonic 3.5 answers faster than both Deepgram models at that percentile, and it is the only one of the three whose spread stays narrow enough to be predictable.
Latency at P95
Lower is better
Accuracy
Sonic 3.6 makes fewer word errors than both Deepgram models
- Coval transcribes every clip each model generates and compares it with the script, so a lower rate means more of the script is spoken as written.
- Sonic 3.6 misreads fewer words than Flux and Aura-2, so names, numbers, and codes come through as written.
Word error rate
Lower is better
Reasons why companies choose Cartesia over Deepgram
Consistency
At scale, the spread in latency matters more than the average.
Cartesia63ms interquartile rangeDeepgram211ms interquartile rangeAura-2300ms interquartile rangeFluxAugust 2026
Accuracy
Whether names, numbers, and terms come through as written.
Cartesia1.99% word error rateSonic 3.6Deepgram2.20% word error rateFlux2.78% word error rateAura-2September 2026
Languages
Comprehension and trust across a global customer base.
Cartesia44 languages from one model, with region-calibrated accentsDeepgram7 languagesVoice range
How far the catalogue stretches before you need your own voice.
CartesiaFull voice library, instant clone from 10 seconds, professional clone from 30 minutesDeepgram88 preset voicesDeployment
Decides whether regulated teams can use it at all.
CartesiaVPC, on-prem, on-device, or air-gapped, backed by a 99.9% uptime SLADeepgramSelf-hosting requires an Enterprise plan
Frequently asked questions
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