Deepgram FluxvsGradium TTS

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
  • Deepgram Flux194 ms · 77.4%
  • Gradium TTS76 ms · 79.5%

Deepgram Flux is better on stopping. Gradium TTS is better on non-streaming latency, streaming latency, accuracy, naturalness and price.

Last updated Methodology by Dileep Chagam

Which is better at what

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

MeasureDeepgram FluxGradium TTS
  • Non-streaming latency (median)Gradium TTS is better194 ms76 ms
  • Streaming latency (median)Gradium TTS is better154 ms−64 ms
  • Extra audio after a stopDeepgram Flux is better80 msNo stop message
  • Hard parts read rightGradium TTS is better77.4%79.5%
  • Naturalness (1 to 5)Gradium TTS is better4.164.51
  • Price per 1M charactersGradium TTS is better$45.00$36.00
Hard parts read rightDeepgram FluxGradium TTS
  • Numbers and shorthand7 a.m. · 20% · 36°F · approx.72%77%
  • Codes and addressesSAVE20 · help@north-clinic.org · 1-800-555-019981%77%
  • Read from contextSt. Mary's on Main St. · Dr. Okafor69%67%
  • Medical termslevothyroxine · gastroenterology97%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

MeasureDeepgram FluxGradium TTS
  • Non-streaming latency (median)6 of 262 of 26
  • Streaming latency (median)6 of 181 of 18
  • Extra audio after a stop4 of 6n/a
  • Hard parts read right19 of 2617 of 26
  • Naturalness (1 to 5)26 of 263 of 26
  • Price per 1M characters21 of 2515 of 25

Deepgram Flux vs Gradium TTS FAQ

  • Gradium TTS. Deepgram Flux: 194 ms. Gradium TTS: 76 ms.

  • Gradium TTS. Deepgram Flux: 154 ms. Gradium TTS: −64 ms.

  • Deepgram Flux. Deepgram Flux: 80 ms. Gradium TTS: No stop message.

  • Gradium TTS. Deepgram Flux: 77.4%. Gradium TTS: 79.5%.

  • Gradium TTS. Deepgram Flux: $45.00. Gradium TTS: $36.00.