Agentic
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Model comparison
Grok 4.1 Fast vs Grok 4.3
Updated July 30, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Grok 4.3 has the higher public score estimate, 64.2 versus 50.41, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
1 results are shared. Category rows based on different benchmark sets are marked directional and do not name a winner.
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 4.1 Fast
Grok 4.1 Fast has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Grok 4.1 Fast
Grok 4.1 Fast 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
Grok 4.1 Fast
Grok 4.1 Fast has the lower estimated token cost for this stated workload. Grok 4.1 Fast 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
Grok 4.1 Fast
Grok 4.1 Fast 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
No shared weighted benchmark basis supports a winner.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
No shared weighted benchmark basis supports a winner.
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.
1 Shared
1 Grok 4.3 only
- Shared results
- 1
- Grok 4.1 Fast only
- 0
- Grok 4.3 only
- 1
- Like-for-like categories
- 0 / 8
Category results, on a stated basis
Each row states whether both averages use the same weighted benchmark set. Directional and not-comparable rows remain visible, but they never receive a winner in this template.
Coding
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Reasoning
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Knowledge
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Math
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Multilingual
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Multimodal
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Instruction following
Not comparable- Grok 4.1 Fast
- Not measured
- Grok 4.3
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
| Category | Grok 4.1 Fast | Grok 4.3 | Weighted basis | Reading |
|---|---|---|---|---|
| Agentic | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Coding | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Reasoning | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Knowledge | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Math | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Multilingual | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Multimodal | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Instruction following | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
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.
A shared-evidence shape is not available.
BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.
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
- Grok 4.1 Fast
- $0.00045
- Fits in one request
- Grok 4.3
- $0.0025
- Fits in one request
Grok 4.1 Fast has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Grok 4.1 Fast
- $0.0115
- Fits in one request
- Grok 4.3
- $0.07
- Fits in one request
Grok 4.1 Fast has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Grok 4.1 Fast
- $0.049
- Fits in one request
- Cached input priced at the published list-input rate
- Grok 4.3
- $0.09
- Fits in one request
Grok 4.1 Fast has the lower modeled cost
Grok 4.1 Fast 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.
SpecificationGrok 4.1 FastGrok 4.3
Context window
Maximum documented context; output-token limits may be lower.
Grok 4.1 Fast
2M
Grok 4.3
1M
API model ID
Grok 4.1 Fast
Not sourced
Grok 4.3
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Grok 4.1 Fast
Not published
Grok 4.3
$0.2 per 1M cached input tokens
Documented inputs
Grok 4.1 Fast
Not sourced
Grok 4.3
Not sourced
Documented outputs
Grok 4.1 Fast
Not sourced
Grok 4.3
Not sourced
Provider availability
Grok 4.1 Fast
Not sourced
Grok 4.3
Not sourced
Reasoning profile
Grok 4.1 Fast
Non-Reasoning
Grok 4.3
Reasoning
Weight access
Grok 4.1 Fast
Proprietary
Grok 4.3
Proprietary
License
Grok 4.1 Fast
Proprietary
Grok 4.3
Proprietary
Release date
Grok 4.1 Fast
2025-11-19
Grok 4.3
2026-04-30
If you already use one of these models
- Deployment change
- Both entries list xAI as the provider. Confirm endpoint, model ID, limits, and feature support before switching.
- Quality signal
- Grok 4.3 has the higher public score estimate, 64.2 versus 50.41, but the 90% score intervals overlap.
- Workload cost
- Repository review: $0.0115 vs $0.07. Cache-heavy agent loop: $0.049 vs $0.09.
- Context tradeoff
- Grok 4.1 Fast 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 evidence2 rows
Agentic
Gert Labs
Shared sourceGrok 4.1 Fast47.32%Grok 4.343.86%Grok 4.1 Fast leads this result
ResearchClawBench
Grok 4.1 Fast—Grok 4.312.4%SourceNot directly comparable
Frequently asked questions
Which is better, Grok 4.1 Fast or Grok 4.3?
Grok 4.3 has the higher public score estimate, 64.2 versus 50.41, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.
Which is better for coding, Grok 4.1 Fast or Grok 4.3?
The published evidence does not provide a shared weighted coding basis for both models, so BenchLM does not name a coding winner.
Which is better for agentic tasks, Grok 4.1 Fast or Grok 4.3?
The published evidence does not provide a shared weighted agentic tasks basis for both models, so BenchLM does not name a agentic tasks winner.
Which costs less, Grok 4.1 Fast or Grok 4.3?
For the stated presets, chat costs $0.00045 on Grok 4.1 Fast and $0.0025 on Grok 4.3; repository review costs $0.0115 and $0.07; the cache-heavy agent loop costs $0.049 and $0.09. Grok 4.1 Fast has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, Grok 4.1 Fast or Grok 4.3?
Grok 4.1 Fast has the larger documented context window: 2M, compared with 1M.
Related comparisons
Last updated July 30, 2026
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