Agentic
Like-for-like- Gemini 3 Flash
- 34.0
- Supported · #134/152
- Grok 4.20
- 26.7
- Supported · #145/152
- Basis
- BenchAlign lane · 4 vs 4 public rows
- Reading
- Gemini 3 Flash leads · intervals overlap
Gemini 3 Flash vs Grok 4.20
Updated September 10, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
Grok 4.20 has the higher public score estimate, 67.13 versus 62.2, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
7 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
Share or export
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Coding work
Code generation, repair, and software-engineering tasks
Gemini 3 Flash
Gemini 3 Flash leads on the public coding lane, 41.5 to 28.2, with Supported evidence for both models, although the 90% intervals overlap.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Gemini 3 Flash
Gemini 3 Flash leads on the public agentic lane, 34 to 26.7, with Supported evidence for both models, although the 90% intervals overlap.
Confidence: limited
Long documents
Prompts that approach the documented context limit
Grok 4.20
Grok 4.20 has the larger documented context window.
Confidence: documented
Show secondary and unsupported calls
Chat turn cost
1K fresh input + 500 output tokens
Gemini 3 Flash
Gemini 3 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Gemini 3 Flash
Gemini 3 Flash has the lower estimated token cost for this stated workload. Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate.
Confidence: rate-fallback
Repository review cost
50K fresh input + 3K output tokens
Gemini 3 Flash
Gemini 3 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
4 Gemini 3 Flash only
7 Shared
16 Grok 4.20 only
- Shared results
- 7
- Gemini 3 Flash only
- 4
- Grok 4.20 only
- 16
- Like-for-like categories
- 3 / 8
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
Coding
Like-for-like- Gemini 3 Flash
- 41.5
- Supported · #108/151
- Grok 4.20
- 28.2
- Supported · #141/151
- Basis
- BenchAlign lane · 3 vs 6 public rows
- Reading
- Gemini 3 Flash leads · intervals overlap
Knowledge
Like-for-like- Gemini 3 Flash
- 56.9
- Supported · #45/183
- Grok 4.20
- 49.4
- Supported · #85/183
- Basis
- BenchAlign lane · 2 vs 6 public rows
- Reading
- Gemini 3 Flash leads · intervals overlap
Reasoning
Not comparable- Gemini 3 Flash
- 59.0
- Unranked · 2 rankable rows
- Grok 4.20
- 34.2
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Math
Not comparable- Gemini 3 Flash
- 50.2
- Unranked · 2 rankable rows
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Gemini 3 Flash
- Not ranked
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Gemini 3 Flash
- 75.8
- Unranked · 1 rankable row
- Grok 4.20
- 34.6
- #43/48
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Gemini 3 Flash
- 66.2
- #68/123
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Gemini 3 Flash | Grok 4.20 | Basis | Reading |
|---|---|---|---|---|
| Agentic | 34.0Supported · #134/152 | 26.7Supported · #145/152 | Like-for-likeBenchAlign lane · 4 vs 4 public rows | Gemini 3 Flash leads · intervals overlap |
| Coding | 41.5Supported · #108/151 | 28.2Supported · #141/151 | Like-for-likeBenchAlign lane · 3 vs 6 public rows | Gemini 3 Flash leads · intervals overlap |
| Knowledge | 56.9Supported · #45/183 | 49.4Supported · #85/183 | Like-for-likeBenchAlign lane · 2 vs 6 public rows | Gemini 3 Flash leads · intervals overlap |
| Reasoning | 59.0Unranked · 2 rankable rows | 34.2Unranked · 2 rankable rows | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Math | 50.2Unranked · 2 rankable rows | Not ranked | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 75.8Unranked · 1 rankable row | 34.6#43/48 | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Instruction following | 66.2#68/123 | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign) differ from the provisional-lane categories. Unranked scores sit on the lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
MMLU-Pro (Vals)
Knowledge
LiveCodeBench (Vals)
Coding
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Gemini 3 Flash
- $0.002
- Fits in one request
- Grok 4.20
- $0.005
- Fits in one request
Gemini 3 Flash has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Gemini 3 Flash
- $0.034
- Fits in one request
- Grok 4.20
- $0.118
- Fits in one request
Gemini 3 Flash has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Gemini 3 Flash
- $0.05
- Fits in one request
- Grok 4.20
- $0.5
- Fits in one request
- Cached input priced at the published list-input rate
Gemini 3 Flash has the lower modeled cost
Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationGemini 3 FlashGrok 4.20
Context window
Maximum documented context; output-token limits may be lower.
Gemini 3 Flash
Grok 4.20
2M
API model ID
Gemini 3 Flash
gemini-3-flash-preview
Google Gemini API pricingGrok 4.20
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Gemini 3 Flash
$0.05 per 1M cached input tokens
Google Gemini API pricingGrok 4.20
Not published
Documented inputs
Gemini 3 Flash
Not sourced
Grok 4.20
Not sourced
Documented outputs
Gemini 3 Flash
Not sourced
Grok 4.20
Not sourced
Provider availability
Gemini 3 Flash
Not sourced
Grok 4.20
Not sourced
Reasoning profile
Gemini 3 Flash
Non-Reasoning
Grok 4.20
Reasoning
Weight access
Gemini 3 Flash
Proprietary
Grok 4.20
Proprietary
License
Gemini 3 Flash
Proprietary
Grok 4.20
Proprietary
Release date
Gemini 3 Flash
2025-12-01
Grok 4.20
2026-03-10
If you already use one of these models
- Deployment change
- The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
- Quality signal
- Grok 4.20 has the higher public score estimate, 67.13 versus 62.2, but the 90% score intervals overlap.
- Workload cost
- Repository review: $0.034 vs $0.118. Cache-heavy agent loop: $0.05 vs $0.5.
- Context tradeoff
- Grok 4.20 has the larger documented window (2M).
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence27 rows
Agentic
Claw-Eval
Gemini 3 Flash49.2%SourceGrok 4.20—Not directly comparable
Gert Labs
Shared sourceGemini 3 Flash56.63%Grok 4.2038.36%Gemini 3 Flash leads this result
JobBench
Gemini 3 Flash11.4%SourceGrok 4.20—Not directly comparable
Terminal-Bench 2.1 (Vals)
Gemini 3 Flash53.9%SourceGrok 4.2044.2%SourceGemini 3 Flash leads this result
Terminal-Bench 2.0
Gemini 3 Flash—Grok 4.2047.1%SourceNot directly comparable
DeepSearchQA
Gemini 3 Flash—Grok 4.2062.8%SourceNot directly comparable
Coding
Vibe Code Bench
Shared sourceGemini 3 Flash20.20%Grok 4.204.06%Gemini 3 Flash leads this result
LiveCodeBench (Vals)
Gemini 3 Flash85.6%SourceGrok 4.2084.3%SourceGemini 3 Flash leads this result
SWE-bench (Vals)
Gemini 3 Flash75.0%SourceGrok 4.2072.2%SourceGemini 3 Flash leads this result
LiveCodeBench Pro
Gemini 3 Flash—Grok 4.2074.2%SourceNot directly comparable
SWE-bench Verified
Gemini 3 Flash—Grok 4.2076.7%SourceNot directly comparable
SWE-bench Pro
Gemini 3 Flash—Grok 4.2051.8%SourceNot directly comparable
Reasoning
Knowledge
GPQA Diamond (Vals)
Gemini 3 Flash87.9%SourceGrok 4.2088.6%SourceGrok 4.20 leads this result
MMLU-Pro (Vals)
Gemini 3 Flash88.6%SourceGrok 4.2086.3%SourceGemini 3 Flash leads this result
GPQA-D
Gemini 3 Flash—Grok 4.2088.5%SourceNot directly comparable
HLE w/o tools
Gemini 3 Flash—Grok 4.2031.6%SourceNot directly comparable
HealthBench Hard
Gemini 3 Flash—Grok 4.2020.3%SourceNot directly comparable
MedXpertQA (Text)
Gemini 3 Flash—Grok 4.2050.2%SourceNot directly comparable
Math
Multimodal
MMMU-Pro
Gemini 3 Flash—Grok 4.2075.2%SourceNot directly comparable
CharXiv
Gemini 3 Flash—Grok 4.2060.9%SourceNot directly comparable
ERQA
Gemini 3 Flash—Grok 4.2054.1%SourceNot directly comparable
SimpleVQA
Gemini 3 Flash—Grok 4.2057.4%SourceNot directly comparable
MedXpertQA (MM)
Gemini 3 Flash—Grok 4.2065.8%SourceNot directly comparable
Frequently asked questions
Which is better, Gemini 3 Flash or Grok 4.20?
Grok 4.20 has the higher public score estimate, 67.13 versus 62.2, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.
Which is better for coding, Gemini 3 Flash or Grok 4.20?
Gemini 3 Flash leads the public coding lane, 41.5 to 28.2, with Supported evidence for both models, although the 90% intervals overlap.
Which is better for agentic tasks, Gemini 3 Flash or Grok 4.20?
Gemini 3 Flash leads the public agentic tasks lane, 34 to 26.7, with Supported evidence for both models, although the 90% intervals overlap.
Which costs less, Gemini 3 Flash or Grok 4.20?
For the stated presets, chat costs $0.002 on Gemini 3 Flash and $0.005 on Grok 4.20; repository review costs $0.034 and $0.118; the cache-heavy agent loop costs $0.05 and $0.5. Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, Gemini 3 Flash or Grok 4.20?
Grok 4.20 has the larger documented context window: 2M, compared with 1M.
Related comparisons
Last updated September 10, 2026
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