Model comparison
Gemini 2.5 Pro vs Grok 4.20
Head-to-head evidence from 4 shared benchmark results across 3 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 2.5 Pro #76 (Supported); Grok 4.20 #93 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 2.5 Pro and Grok 4.20 share 4 comparable benchmark results. 1 of 8 categories are comparable. 20 results are unique to Gemini 2.5 Pro; 15 to Grok 4.20.
Updated July 28, 2026- Shared results
- 4
- Gemini 2.5 Pro only
- 20
- Grok 4.20 only
- 15
- Comparable categories
- 1 / 8
Pick Gemini 2.5 Pro if you want the stronger benchmark profile. Grok 4.20 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 4 shared benchmark results across 3 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
Gemini 2.5 Pro has the cleaner BenchAlign overall profile here, landing at 56.6 versus 53.88. It is a real lead, but still close enough that category-level strengths matter more than the headline number.
Gemini 2.5 Pro is also the more expensive model on tokens at $1.25 input / $10.00 output per 1M tokens, versus $2.00 input / $6.00 output per 1M tokens for Grok 4.20. Grok 4.20 is the reasoning model in the pair, while Gemini 2.5 Pro 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 4.20 gives you the larger context window at 2M, compared with 1M for Gemini 2.5 Pro.
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 | Gemini 2.5 Pro | Δ | Grok 4.20 |
|---|---|---|---|
| Coding | Gemini 2.5 Pro63.8 | Margin→ 3.3 | Grok 4.2067.1 |
| Agentic | Gemini 2.5 ProNot measured | MarginNo overlap | Grok 4.2047.1 |
| Reasoning | Gemini 2.5 ProNot measured | MarginNo overlap | Grok 4.2053.3 |
| Knowledge | Gemini 2.5 Pro27.4 | MarginNo overlap | Grok 4.20Not measured |
| Math | Gemini 2.5 Pro11.6 | MarginNo overlap | Grok 4.20Not measured |
| Multimodal | Gemini 2.5 ProNot measured | MarginNo overlap | Grok 4.2070.1 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 63.8%B 76.7%Winner: Grok 4.20Δ 12.9SWE-bench Verified: Gemini 2.5 Pro scored 63.8%; Grok 4.20 scored 76.7%. Grok 4.20 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 2.5 Pro | Grok 4.20 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 2.5 Pro$1.25 input / $10 output | Grok 4.20$2 input / $6 output | Grok 4.20 has the lower combined listed price. |
| Generation speedtokens per second | Gemini 2.5 Pro117 tok/s | Grok 4.20233 tok/s | Grok 4.20 has the higher measured throughput. |
| First-answer latencyseconds to first token | Gemini 2.5 Pro21.19 s | Grok 4.2010.33 s | Grok 4.20 reaches the first token sooner. |
| Context windowmaximum listed tokens | Gemini 2.5 Pro1M | Grok 4.202M | Grok 4.20 lists the larger context window. |
Benchmark Deep Dive
Agentic7 benchmarks
| Benchmark | Gemini 2.5 Pro | Grok 4.20 | Result |
|---|---|---|---|
| AA Agentic IndexSource | 7.1% | — | Not comparable |
| τ²-bench resultsSource | 54.1% | — | Not comparable |
| Gert LabsSource | 42.01% | 38.36% | Gemini 2.5 Pro leads |
| GDPval-AASource | 8.6% | — | Not comparable |
| GDPval-AASource | 672 | — | Not comparable |
| Terminal-Bench 2.0Source | — | 47.1% | Not comparable |
| DeepSearchQASource | — | 62.8% | Not comparable |
CodingGrok 4.20 wins6 benchmarks
Reasoning4 benchmarks
Knowledge12 benchmarks
| Benchmark | Gemini 2.5 Pro | Grok 4.20 | Result |
|---|---|---|---|
| GPQASource | 83% | — | Not comparable |
| HLESource | 18.8% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 25.8% | — | Not comparable |
| AA-GPQA DiamondSource | 84.4% | — | Not comparable |
| AA-HLESource | 21.1% | — | Not comparable |
| AA-Omniscience IndexSource | -14.3% | — | Not comparable |
| AA-Omniscience AccuracySource | 39.0% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 87.4% | — | Not comparable |
| GPQA-DSource | — | 88.5% | Not comparable |
| HLE w/o toolsSource | — | 31.6% | Not comparable |
| HealthBench HardSource | — | 20.3% | Not comparable |
| MedXpertQA (Text)Source | — | 50.2% | Not comparable |
Math2 benchmarks
Multimodal7 benchmarks
| Benchmark | Gemini 2.5 Pro | Grok 4.20 | Result |
|---|---|---|---|
| AA-MMMU-ProSource | 74.9% | — | Not comparable |
| Design Arena WebsiteSource | 1192 | 1252 | Grok 4.20 leads |
| MMMU-ProSource | — | 75.2% | Not comparable |
| CharXivSource | — | 60.9% | Not comparable |
| ERQASource | — | 54.1% | Not comparable |
| SimpleVQASource | — | 57.4% | Not comparable |
| MedXpertQA (MM)Source | — | 65.8% | Not comparable |
Inst. Following1 benchmarks
| Benchmark | Gemini 2.5 Pro | Grok 4.20 | Result |
|---|---|---|---|
| AA-IFBenchSource | 48.7% | — | Not comparable |
Frequently Asked Questions (2)
Which is better, Gemini 2.5 Pro or Grok 4.20?
Gemini 2.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 56.6 to 53.88. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 63.8% and 76.7%.
Which is better for coding, Gemini 2.5 Pro or Grok 4.20?
Grok 4.20 has the edge for coding in this comparison, averaging 67.1 versus 63.8. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
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