Model comparison
Grok 4.3 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: Grok 4.3 #31 (Supported); Grok Code Fast 1 #180 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Grok 4.3 and Grok Code Fast 1 share 11 comparable benchmark results. 1 of 8 categories are comparable. 14 results are unique to Grok 4.3; 1 to Grok Code Fast 1.
Updated July 23, 2026- Shared results
- 11
- Grok 4.3 only
- 14
- Grok Code Fast 1 only
- 1
- Comparable categories
- 1 / 8
Pick Grok 4.3 if you want the stronger benchmark profile. Grok Code Fast 1 only becomes the better choice if coding is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 11 shared benchmark results across 5 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Grok 4.3 is clearly ahead on the BenchAlign aggregate, 65.1 to 38.64. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Grok 4.3 is also the more expensive model on tokens at $1.25 input / $2.50 output per 1M tokens, versus $0.20 input / $1.50 output per 1M tokens for Grok Code Fast 1. Grok 4.3 is the reasoning model in the pair, while Grok Code Fast 1 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Grok 4.3 gives you the larger context window at 1M, compared with 256K for Grok Code Fast 1.
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 | Grok 4.3 | Δ | Grok Code Fast 1 |
|---|---|---|---|
| Coding | Grok 4.347.3 | Margin→ 23.5 | Grok Code Fast 170.8 |
| Knowledge | Grok 4.342.4 | MarginNo overlap | Grok Code Fast 1Not measured |
| Multimodal | Grok 4.378.1 | MarginNo overlap | Grok Code Fast 1Not measured |
| Inst. Following | Grok 4.381.3 | MarginNo overlap | Grok Code Fast 1Not measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Grok 4.3 | Grok Code Fast 1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Grok 4.3$1.25 input / $2.5 output | Grok Code Fast 1$0.2 input / $1.5 output | Grok Code Fast 1 has the lower combined listed price. |
| Generation speedtokens per second | Grok 4.3209 tok/s | Grok Code Fast 1172 tok/s | Grok 4.3 has the higher measured throughput. |
| First-answer latencyseconds to first token | Grok 4.312.36 s | Grok Code Fast 12.81 s | Grok Code Fast 1 reaches the first token sooner. |
| Context windowmaximum listed tokens | Grok 4.31M | Grok Code Fast 1256K | Grok 4.3 lists the larger context window. |
Benchmark Deep Dive
Agentic7 benchmarks
| Benchmark | Grok 4.3 | Grok Code Fast 1 | Result |
|---|---|---|---|
| τ²-bench resultsSource | 97.7% | 75.7% | Grok 4.3 leads |
| GDPval-AASource | 29.2% | — | Not comparable |
| AA Agentic IndexSource | 24.1% | — | Not comparable |
| APEX-Agents-AASource | 17.0% | — | Not comparable |
| GDPval-AASource | 1085 | — | Not comparable |
| Gert LabsSource | 43.86% | — | Not comparable |
| ResearchClawBenchSource | 12.4% | — | Not comparable |
CodingGrok Code Fast 1 wins4 benchmarks
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Grok 4.3 | Grok Code Fast 1 | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 37.6% | 21.6% | Grok 4.3 leads |
| GPQASource | 90.1% | — | Not comparable |
| HLESource | 35% | — | Not comparable |
| AA-Omniscience AccuracySource | 34.6% | 23.8% | Grok 4.3 leads |
| AA-Omniscience Hallucination RateSource | 25.0% | 78.5% | Grok 4.3 leads |
| AA-GPQA DiamondSource | 90.1% | 72.7% | Grok 4.3 leads |
| AA-HLESource | 35.0% | 7.5% | Grok 4.3 leads |
| AA-Omniscience IndexSource | 18.3% | -36.0% | Grok 4.3 leads |
Multimodal3 benchmarks
Frequently Asked Questions (2)
Which is better, Grok 4.3 or Grok Code Fast 1?
Grok 4.3 is ahead on BenchLM's BenchAlign leaderboard, 65.1 to 38.64.
Which is better for coding, Grok 4.3 or Grok Code Fast 1?
Grok Code Fast 1 has the edge for coding in this comparison, averaging 70.8 versus 47.3. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.
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