Model comparison
GPT-OSS 20B vs Grok Code Fast 1
Head-to-head evidence from 11 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-OSS 20B #159 (Supported); Grok Code Fast 1 #180 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-OSS 20B and Grok Code Fast 1 share 11 comparable benchmark results. 0 of 8 categories are comparable. 7 results are unique to GPT-OSS 20B; 1 to Grok Code Fast 1.
Updated July 20, 2026- Shared results
- 11
- GPT-OSS 20B only
- 7
- Grok Code Fast 1 only
- 1
- Comparable categories
- 0 / 8
Benchmark data for GPT-OSS 20B and Grok Code Fast 1 is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 11 shared benchmark results across 5 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Grok Code Fast 1 is priced at $0.20 input / $1.50 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for GPT-OSS 20B. Grok Code Fast 1 has the larger context window at 256K, compared with 128K for GPT-OSS 20B.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | GPT-OSS 20B | Δ | Grok Code Fast 1 |
|---|---|---|---|
| Coding | GPT-OSS 20BNot measured | MarginNo overlap | Grok Code Fast 170.8 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-OSS 20B | Grok Code Fast 1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-OSS 20B$0 input / $0 output | Grok Code Fast 1$0.2 input / $1.5 output | GPT-OSS 20B has the lower combined listed price. |
| Generation speedtokens per second | GPT-OSS 20B313 tok/s | Grok Code Fast 1172 tok/s | GPT-OSS 20B has the higher measured throughput. |
| First-answer latencyseconds to first token | GPT-OSS 20B0.65 s | Grok Code Fast 12.81 s | GPT-OSS 20B reaches the first token sooner. |
| Context windowmaximum listed tokens | GPT-OSS 20B128K | Grok Code Fast 1256K | Grok Code Fast 1 lists the larger context window. |
Benchmark Deep Dive
Agentic5 benchmarks
Coding4 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | GPT-OSS 20B | Grok Code Fast 1 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 14.9% | 21.6% | Grok Code Fast 1 leads |
| AA-GPQA DiamondSource | 68.8% | 72.7% | Grok Code Fast 1 leads |
| AA-HLESource | 9.8% | 7.5% | GPT-OSS 20B leads |
| AA-Omniscience IndexSource | -63.9% | -36.0% | Grok Code Fast 1 leads |
| AA-Omniscience AccuracySource | 15.5% | 23.8% | Grok Code Fast 1 leads |
| AA-Omniscience Hallucination RateSource | 94.1% | 78.5% | Grok Code Fast 1 leads |
Multimodal1 benchmarks
| Benchmark | GPT-OSS 20B | Grok Code Fast 1 | Result |
|---|---|---|---|
| Design Arena WebsiteSource | 885 | — | Not comparable |
Inst. Following1 benchmarks
| Benchmark | GPT-OSS 20B | Grok Code Fast 1 | Result |
|---|---|---|---|
| AA-IFBenchSource | 65.1% | 41.4% | GPT-OSS 20B leads |
Frequently Asked Questions (3)
Can I compare GPT-OSS 20B and Grok Code Fast 1 on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for GPT-OSS 20B and Grok Code Fast 1 today?
GPT-OSS 20B: $0.00 input / $0.00 output per 1M tokens Grok Code Fast 1: $0.20 input / $1.50 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
Related Comparisons
Explore More
Choose a model with this week’s evidence
Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.
One email each week. Unsubscribe anytime.