Mistral AI vs Grok Speech (STT + TTS APIs)

Which one should you pick? Here's the full breakdown.

Mistral AI

B
7.5/10

European AI lab with open and commercial models -- Mistral Small 4 (Mar 2026, 119B MoE Apache 2.0 unified model), Medium 3 (Apr 9 2026), and Voxtral TTS (open-source speech, Mar 2026)

Our Pick

Grok Speech (STT + TTS APIs)

A
8.1/10

xAI's standalone voice APIs -- launched 2026-04-17. Built on the stack that powers Grok Voice, Tesla vehicles, and Starlink customer support. $0.10/hr STT batch, $4.20 per 1M characters TTS, 25+ languages, word-level timestamps + speaker diarization

CategoryMistral AIGrok Speech (STT + TTS APIs)
Ease of Use6.07.0
Output Quality8.08.5
Value9.09.0
Features7.08.0
Overall7.58.1

Pricing Comparison

FeatureMistral AIGrok Speech (STT + TTS APIs)
Free TierYesNo
Starting Price$0$0.10

Benchmark Head-to-Head

Mistral Large 3 / Small 4 benchmarks — Grok Speech (STT + TTS APIs) has no published benchmarks

BenchmarkScore
MMLU86%
HumanEval92%
MATH69%

Which Should You Pick?

Pick Mistral AI if...

  • Has a free tier

Developers who want cheap, high-quality API access. Also strong for multilingual applications and European companies that prefer an EU-based AI provider for data residency.

Visit Mistral AI

Pick Grok Speech (STT + TTS APIs) if...

  • Easier to use (7 vs 6)
  • More features (8 vs 7)

Developers building voice agents, real-time transcription tools, accessibility features, or high-volume TTS workloads where the cost per hour of audio actually matters at scale. Strong fit for phone-call and meeting transcription use cases where xAI's published WER advantage (5.0% on phone-call entities vs. ElevenLabs 12.0%) compounds quickly.

Visit Grok Speech (STT + TTS APIs)

Our Verdict

Grok Speech (STT + TTS APIs) edges out Mistral AI with a 8.1 vs 7.5 overall score. Both are solid picks, but Grok Speech (STT + TTS APIs) has the advantage in output quality.