gpt-oss (OpenAI) vs Grok Speech (STT + TTS APIs)

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

Our Pick

gpt-oss (OpenAI)

A
8.1/10

OpenAI's FIRST open-weight models -- gpt-oss-120b (single 80GB GPU, near parity with o4-mini on reasoning) and gpt-oss-20b (runs on 16GB edge devices). Apache 2.0. Launched 2025-08-05. gpt-oss-safeguard ships in 2026 as the safety-tuned variant

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

Categorygpt-oss (OpenAI)Grok Speech (STT + TTS APIs)
Ease of Use7.07.0
Output Quality8.58.5
Value10.09.0
Features7.08.0
Overall8.18.1

Pricing Comparison

Featuregpt-oss (OpenAI)Grok Speech (STT + TTS APIs)
Free TierYesNo
Starting Price$0$0.10

Which Should You Pick?

Pick gpt-oss (OpenAI) if...

  • Better value for money (10/10)
  • Has a free tier

Developers who want OpenAI-brand open-weight reasoning models for self-hosting or fine-tuning. Particularly good for single-GPU deployments (gpt-oss-120b on one 80GB card) or edge-device reasoning (gpt-oss-20b on 16GB consumer GPUs / Apple Silicon). Also good as a reliable baseline when comparing newer open-weight releases.

Visit gpt-oss (OpenAI)

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

  • 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

gpt-oss (OpenAI) and Grok Speech (STT + TTS APIs) are extremely close overall. Your choice comes down to specific needs -- gpt-oss (OpenAI) is better for developers who want openai-brand open-weight reasoning models for self-hosting or fine-tuning, while Grok Speech (STT + TTS APIs) works best for 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.