Agentic
Directional only- Gemini 3.1 Flash-Lite
- 42.9
- Estimated · #101/152
- Grok 4.20
- 26.7
- Supported · #145/152
- Basis
- BenchAlign lane · 2 vs 4 public rows
- Reading
- Directional only
Gemini 3.1 Flash-Lite 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 56.19, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
8 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.
Long documents
Prompts that approach the documented context limit
Grok 4.20
Grok 4.20 has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Gemini 3.1 Flash-Lite
Gemini 3.1 Flash-Lite 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 3.1 Flash-Lite
Gemini 3.1 Flash-Lite 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
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
Gemini 3.1 Flash-Lite
Gemini 3.1 Flash-Lite has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
Gemini 3.1 Flash-Lite is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
Gemini 3.1 Flash-Lite is scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.
Confidence: limited
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
8 Shared
15 Grok 4.20 only
- Shared results
- 8
- Gemini 3.1 Flash-Lite only
- 0
- Grok 4.20 only
- 15
- Like-for-like categories
- 0 / 8
3 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.
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
Directional only- Gemini 3.1 Flash-Lite
- 37.9
- Estimated · #124/151
- Grok 4.20
- 28.2
- Supported · #141/151
- Basis
- BenchAlign lane · 3 vs 6 public rows
- Reading
- Directional only
Knowledge
Directional only- Gemini 3.1 Flash-Lite
- 51.5
- Estimated · #71/183
- Grok 4.20
- 49.4
- Supported · #85/183
- Basis
- BenchAlign lane · 2 vs 6 public rows
- Reading
- Directional only
Reasoning
Not comparable- Gemini 3.1 Flash-Lite
- Not ranked
- Grok 4.20
- 34.2
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Math
Not comparable- Gemini 3.1 Flash-Lite
- Not ranked
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Gemini 3.1 Flash-Lite
- Not ranked
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Gemini 3.1 Flash-Lite
- 37.5
- Unranked · 1 rankable row
- Grok 4.20
- 34.6
- #43/48
- Basis
- Provisional lane · 1 vs 2 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Gemini 3.1 Flash-Lite
- Not ranked
- Grok 4.20
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Gemini 3.1 Flash-Lite | Grok 4.20 | Basis | Reading |
|---|---|---|---|---|
| Agentic | 42.9Estimated · #101/152 | 26.7Supported · #145/152 | Directional onlyBenchAlign lane · 2 vs 4 public rows | Directional only |
| Coding | 37.9Estimated · #124/151 | 28.2Supported · #141/151 | Directional onlyBenchAlign lane · 3 vs 6 public rows | Directional only |
| Knowledge | 51.5Estimated · #71/183 | 49.4Supported · #85/183 | Directional onlyBenchAlign lane · 2 vs 6 public rows | Directional only |
| Reasoning | Not ranked | 34.2Unranked · 2 rankable rows | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Math | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 37.5Unranked · 1 rankable row | 34.6#43/48 | Not comparableProvisional lane · 1 vs 2 weighted rows | Not comparable |
| Instruction following | Not ranked | 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.
CharXiv
Multimodal
Gemini 3.1 Flash-Lite: 73.2%Grok 4.20: 60.9%Normalized gap 12.3Gemini 3.1 Flash-Lite source Grok 4.20 sourceLiveCodeBench (Vals)
Coding
Gemini 3.1 Flash-Lite: 80.1%Grok 4.20: 84.3%Normalized gap 4.2Gemini 3.1 Flash-Lite source Grok 4.20 sourceMMLU-Pro (Vals)
Knowledge
Gemini 3.1 Flash-Lite: 86.2%Grok 4.20: 86.3%Normalized gap 0.1Gemini 3.1 Flash-Lite source Grok 4.20 source
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 3.1 Flash-Lite
- $0.001
- Fits in one request
- Grok 4.20
- $0.005
- Fits in one request
Gemini 3.1 Flash-Lite has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Gemini 3.1 Flash-Lite
- $0.017
- Fits in one request
- Grok 4.20
- $0.118
- Fits in one request
Gemini 3.1 Flash-Lite 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 3.1 Flash-Lite
- $0.025
- Fits in one request
- Grok 4.20
- $0.5
- Fits in one request
- Cached input priced at the published list-input rate
Gemini 3.1 Flash-Lite 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 3.1 Flash-LiteGrok 4.20
Context window
Maximum documented context; output-token limits may be lower.
Gemini 3.1 Flash-Lite
Grok 4.20
2M
API model ID
Gemini 3.1 Flash-Lite
gemini-3.1-flash-lite
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 3.1 Flash-Lite
$0.025 per 1M cached input tokens
Google Gemini API pricingGrok 4.20
Not published
Documented inputs
Gemini 3.1 Flash-Lite
Not sourced
Grok 4.20
Not sourced
Documented outputs
Gemini 3.1 Flash-Lite
Not sourced
Grok 4.20
Not sourced
Provider availability
Gemini 3.1 Flash-Lite
Not sourced
Grok 4.20
Not sourced
Reasoning profile
Gemini 3.1 Flash-Lite
Non-Reasoning
Grok 4.20
Reasoning
Weight access
Gemini 3.1 Flash-Lite
Proprietary
Grok 4.20
Proprietary
License
Gemini 3.1 Flash-Lite
Proprietary
Grok 4.20
Proprietary
Release date
Gemini 3.1 Flash-Lite
2026-03-03
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 56.19, but the 90% score intervals overlap.
- Workload cost
- Repository review: $0.017 vs $0.118. Cache-heavy agent loop: $0.025 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 evidence23 rows
Agentic
Gert Labs
Shared sourceGemini 3.1 Flash-Lite38.46%Grok 4.2038.36%Gemini 3.1 Flash-Lite leads this result
Terminal-Bench 2.1 (Vals)
Gemini 3.1 Flash-Lite34.1%SourceGrok 4.2044.2%SourceGrok 4.20 leads this result
Terminal-Bench 2.0
Gemini 3.1 Flash-Lite—Grok 4.2047.1%SourceNot directly comparable
DeepSearchQA
Gemini 3.1 Flash-Lite—Grok 4.2062.8%SourceNot directly comparable
Coding
Vibe Code Bench
Shared sourceGemini 3.1 Flash-Lite0.00%Grok 4.204.06%Grok 4.20 leads this result
LiveCodeBench (Vals)
Gemini 3.1 Flash-Lite80.1%SourceGrok 4.2084.3%SourceGrok 4.20 leads this result
SWE-bench (Vals)
Gemini 3.1 Flash-Lite62.8%SourceGrok 4.2072.2%SourceGrok 4.20 leads this result
LiveCodeBench Pro
Gemini 3.1 Flash-Lite—Grok 4.2074.2%SourceNot directly comparable
SWE-bench Verified
Gemini 3.1 Flash-Lite—Grok 4.2076.7%SourceNot directly comparable
SWE-bench Pro
Gemini 3.1 Flash-Lite—Grok 4.2051.8%SourceNot directly comparable
Reasoning
Knowledge
GPQA Diamond (Vals)
Gemini 3.1 Flash-Lite81.1%SourceGrok 4.2088.6%SourceGrok 4.20 leads this result
MMLU-Pro (Vals)
Gemini 3.1 Flash-Lite86.2%SourceGrok 4.2086.3%SourceGrok 4.20 leads this result
GPQA-D
Gemini 3.1 Flash-Lite—Grok 4.2088.5%SourceNot directly comparable
HLE w/o tools
Gemini 3.1 Flash-Lite—Grok 4.2031.6%SourceNot directly comparable
HealthBench Hard
Gemini 3.1 Flash-Lite—Grok 4.2020.3%SourceNot directly comparable
MedXpertQA (Text)
Gemini 3.1 Flash-Lite—Grok 4.2050.2%SourceNot directly comparable
Multimodal
CharXiv
Gemini 3.1 Flash-Lite73.2%SourceGrok 4.2060.9%SourceGemini 3.1 Flash-Lite leads this result
MMMU-Pro
Gemini 3.1 Flash-Lite—Grok 4.2075.2%SourceNot directly comparable
ERQA
Gemini 3.1 Flash-Lite—Grok 4.2054.1%SourceNot directly comparable
SimpleVQA
Gemini 3.1 Flash-Lite—Grok 4.2057.4%SourceNot directly comparable
MedXpertQA (MM)
Gemini 3.1 Flash-Lite—Grok 4.2065.8%SourceNot directly comparable
Frequently asked questions
Which is better, Gemini 3.1 Flash-Lite or Grok 4.20?
Grok 4.20 has the higher public score estimate, 67.13 versus 56.19, 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 3.1 Flash-Lite or Grok 4.20?
Gemini 3.1 Flash-Lite scores higher for coding on the public lane, 37.9 to 28.2. Gemini 3.1 Flash-Lite is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.
Which is better for agentic tasks, Gemini 3.1 Flash-Lite or Grok 4.20?
Gemini 3.1 Flash-Lite scores higher for agentic tasks on the public lane, 42.9 to 26.7. Gemini 3.1 Flash-Lite is scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.
Which costs less, Gemini 3.1 Flash-Lite or Grok 4.20?
For the stated presets, chat costs $0.001 on Gemini 3.1 Flash-Lite and $0.005 on Grok 4.20; repository review costs $0.017 and $0.118; the cache-heavy agent loop costs $0.025 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 3.1 Flash-Lite 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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