Model comparison
GPT-5.3-Codex-Spark vs Grok Code Fast 1
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.3-Codex-Spark #79 (Estimated); Grok Code Fast 1 #189 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.3-Codex-Spark and Grok Code Fast 1 share 0 comparable benchmark results. 0 of 8 categories are comparable. 0 results are unique to GPT-5.3-Codex-Spark; 12 to Grok Code Fast 1.
Updated July 28, 2026- Shared results
- 0
- GPT-5.3-Codex-Spark only
- 0
- Grok Code Fast 1 only
- 12
- Comparable categories
- 0 / 8
Benchmark data for GPT-5.3-Codex-Spark and Grok Code Fast 1 is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 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 does not have sourced benchmark coverage for GPT-5.3-Codex-Spark yet. This comparison is currently limited to metadata such as context window, reasoning mode, and pricing where available.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.3-Codex-Spark | Grok Code Fast 1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.3-Codex-SparkNot available | Grok Code Fast 1$0.2 input / $1.5 output | A complete price comparison is not available. |
| Generation speedtokens per second | GPT-5.3-Codex-SparkNot available | Grok Code Fast 1172 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.3-Codex-SparkNot available | Grok Code Fast 12.81 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.3-Codex-Spark256K | Grok Code Fast 1256K | Listed context windows are equal. |
Benchmark Deep Dive
Agentic1 benchmarks
| Benchmark | GPT-5.3-Codex-Spark | Grok Code Fast 1 | Result |
|---|---|---|---|
| τ²-bench resultsSource | — | 75.7% | Not comparable |
Coding2 benchmarks
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | GPT-5.3-Codex-Spark | Grok Code Fast 1 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | — | 21.6% | Not comparable |
| AA-GPQA DiamondSource | — | 72.7% | Not comparable |
| AA-HLESource | — | 7.5% | Not comparable |
| AA-Omniscience IndexSource | — | -36.0% | Not comparable |
| AA-Omniscience AccuracySource | — | 23.8% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 78.5% | Not comparable |
Inst. Following1 benchmarks
| Benchmark | GPT-5.3-Codex-Spark | Grok Code Fast 1 | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 41.4% | Not comparable |
Frequently Asked Questions (3)
Can I compare GPT-5.3-Codex-Spark 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-5.3-Codex-Spark and Grok Code Fast 1 today?
GPT-5.3-Codex-Spark: Pricing unavailable 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.
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