gpt-oss-120b vs Grok 4.3

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

gpt-oss-120b

OpenAI · Aug 2025

OpenAI's open-weights MoE reasoning model under Apache 2.0 — near o4-mini quality, runnable on a single 80GB GPU.

Grok 4.3

xAI · Apr 2026

xAI's frontier model: 1M context at $1.25/$2.50, ~168 tokens/sec, and a record low hallucination rate on independent testing.

The verdict

These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: gpt-oss-120b works out roughly 7.8x cheaper per blended million tokens. Grok 4.3 also takes 1M of context versus 131K for gpt-oss-120b. And gpt-oss-120b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.

Specs & pricing

gpt-oss-120bGrok 4.3
modhub Index
Input price / 1M$0.1$1.25
Output price / 1M$0.5$2.5
Context window131K1M
Max output131K
Open weightsyes (Apache 2.0)no
Reasoning modelyesyes
Multimodal inputtexttext, image
Knowledge cutoffJun 2024Mar 2026
ReleasedAug 2025Apr 2026
Example monthly cost*$1.75$16.25

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, gpt-oss-120b or Grok 4.3?
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: gpt-oss-120b works out roughly 7.8x cheaper per blended million tokens. Grok 4.3 also takes 1M of context versus 131K for gpt-oss-120b. And gpt-oss-120b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Which is cheaper, gpt-oss-120b or Grok 4.3?
gpt-oss-120b costs $0.1/$0.5 per million input/output tokens, while Grok 4.3 costs $1.25/$2.5. For a typical workload of 10M input and 1.5M output tokens per month, that's $1.75 versus $16.25.
Which model is better for coding, gpt-oss-120b or Grok 4.3?
We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.

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