TTS alternatives · 2026
Best Cartesia alternatives for real-time TTS
Every model from another provider that Coval measures, ordered by speed (speed tier, then P95 time to first audio), against Cartesia's fastest measured model, Cartesia Sonic 3.5. Voice quality, accuracy and price are side by side, never added into one score.
Data read October 22, 2026 · Coval, Speko, Artificial Analysis
| Model | Speed tier | Median (Coval) | P95 (Coval) | Listener Elo (AA) | Price / 1M chars |
|---|---|---|---|---|---|
| Cartesia Sonic 3.5Cartesia · reference | Visible delay | 281 ms | 381 ms | 1,191 ±11 | $49 to $50 |
| Alibaba Qwen3 TTS 1.7bAlibaba (Qwen) | Fast enough | 104 ms | 138 ms | not rated | not published |
| Alibaba Qwen3 TTS FastAlibaba (Qwen) | Headroom | 64 ms | 97 ms | not rated | $10 |
| Alibaba Qwen3 TTS Flash RealtimeAlibaba (Qwen) | Visible delay | 728 ms | 789 ms | not rated | $13 |
| Deepdub Phantom Z 3.4 conversationalDeepdub | Visible delay | 238 ms | 432 ms | not rated | not published |
| Deepgram Aura 2Deepgram | Visible delay | 266 ms | 526 ms | not rated | $30 |
| Deepgram Aura 2 EnDeepgram | Visible delay | 520 ms | 1,027 ms | not rated | not published |
| Deepgram Flux TTSDeepgram | Fast enough | 200 ms | 263 ms | 1,052 ±13 | $45 |
| ElevenLabs Eleven v4 TurboElevenLabs | Fast enough | 190 ms | 244 ms | 1,335 ±17 | $40 |
| ElevenLabs Flash v2.5ElevenLabs | Fast enough | 188 ms | 241 ms | 1,077 ±11 | $40 to $50 |
| Fish Audio Drama 3 PreviewFish Audio | Fast enough | 146 ms | 213 ms | 1,248 ±15 | $15 |
| Fish Audio S2.1 ProFish Audio | Visible delay | 318 ms | 568 ms | 1,189 ±14 | $15 |
| Fish Audio S2.1 Pro FreeFish Audio | Visible delay | 836 ms | 1,159 ms | not rated | not published |
| Fluxions vuiFluxions | Headroom | 41 ms | 83 ms | not rated | $9 |
| Google Chirp 3: HDGoogle | Visible delay | 534 ms | 917 ms | 1,061 ±12 | $30 |
| Gradium TTSGradium | Headroom | 55 ms | 101 ms | 1,176 ±13 | $35.9 to $57.8 |
| Guava Daytona TTSGuava | Visible delay | 466 ms | 595 ms | not rated | not published |
| Inworld Realtime TTS-2Inworld | Fast enough | 153 ms | 200 ms | 1,267 ±15 | $15 to $25 |
| Inworld Realtime TTS-2 FlashInworld | Headroom | 61 ms | 98 ms | 1,218 ±13 | $10.4 to $15 |
| Murf AI Falcon 2Murf AI | Visible delay | 286 ms | 613 ms | 1,153 ±13 | $10 |
| OpenAI GPT-4o mini TTSOpenAI | Visible delay | 950 ms | 5,055 ms | not rated | $20 |
| Out of Set Airy TTSOut of Set | Visible delay | 216 ms | 467 ms | not rated | $3.67 |
| Palabra TTS v1Palabra | Fast enough | 109 ms | 205 ms | not rated | $12 |
| Rime CodaRime | Visible delay | 300 ms | 415 ms | 1,056 ±12 | $50 |
| Rime Mist v3Rime | Visible delay | 258 ms | 346 ms | not rated | $30 |
| Smallest.ai Lightning V3.1 Pro (Jul 2026)Smallest.ai | Visible delay | 356 ms | 691 ms | 1,169 ±12 | $19.5 |
| Soniox TTS Real-Time v2Soniox | Visible delay | 263 ms | 325 ms | 1,180 ±11 | $13 to $14.2 |
| Soniox TTS RT v1Soniox | Visible delay | 260 ms | 320 ms | not rated | $13 to $14.1 |
| SpaceXAI Grok TTSxAI | Visible delay | 358 ms | 489 ms | 1,150 ±13 | $15 |
| SpeechifyAI Simba 3.0Speechify | Fast enough | 101 ms | 148 ms | 1,121 ±11 | $6.6 to $10 |
| SpeechifyAI Simba 3.2Speechify | Fast enough | 106 ms | 172 ms | 1,245 ±12 | $6.6 to $10 |
Head to head: Gradium TTS vs Cartesia Sonic 3.5 · which TTS APIs are fast enough for voice agents
Frequently asked questions
- What are the fastest alternatives to Cartesia for real-time text-to-speech?
- On Coval's 30-day window read on October 22, 2026, Cartesia Sonic 3.5 starts speaking in 381 ms on slow turns (P95). 16 models from other providers are faster by 10 ms or more, starting with Alibaba Qwen3 TTS 1.7b (138 ms), Alibaba Qwen3 TTS Fast (97 ms), Deepgram Flux TTS (263 ms) and ElevenLabs Eleven v4 Turbo (244 ms).
- Which alternatives to Cartesia sound more natural?
- Artificial Analysis rates Cartesia Sonic 3.5 at 1,191 ±11 Elo. Among the alternatives Coval measures, 5 are rated higher with no overlap of the 95% intervals: ElevenLabs Eleven v4 Turbo (1,335 ±17), Fish Audio Drama 3 Preview (1,248 ±15), Inworld Realtime TTS-2 (1,267 ±15) and Inworld Realtime TTS-2 Flash (1,218 ±13).
- Are there cheaper alternatives to Cartesia?
- Cartesia Sonic 3.5 lists at $49 to $50 per 1M characters. 24 of the alternatives Coval measures list lower, for example Alibaba Qwen3 TTS Fast ($10), Alibaba Qwen3 TTS Flash Realtime ($13), Deepgram Aura 2 ($30) and Deepgram Flux TTS ($45).
- How are these Cartesia alternatives ordered?
- Speed first, as everywhere on this site: by speed tier on Coval's P95 time to first audio, then by P95. Voice quality, accuracy and price are shown side by side and never added into one score. Cartesia's own models are left out.