Claude 3.7 Sonnet vs Grok-4.1 Fast Reasoning
Comparing Claude 3.7 Sonnet and Grok-4.1 Fast Reasoning across benchmarks, pricing, and capabilities.
Anthropic · xAI · Updated for 2026
Which is better?
Claude 3.7 Sonnet and Grok-4.1 Fast Reasoning trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, Grok-4.1 Fast Reasoning is roughly 21.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Grok-4.1 Fast Reasoning also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current benchmark, pricing, and model metadata for 2026.
Choose Claude 3.7 Sonnet
- you want predictable pricing at $3.00/M input and $15.00/M output
Choose Grok-4.1 Fast Reasoning
- cost matters — it's about 21.8x cheaper per token
- you process long inputs — it offers a 2,000,000 token context window
- you want the most recent training data — it shipped Nov 2025
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Claude 3.7 Sonnet and Grok-4.1 Fast Reasoningdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude 3.7 Sonnet ($3.00/1M tokens) is 15.0x more expensive than Grok-4.1 Fast Reasoning ($0.20/1M tokens).
For output processing, Claude 3.7 Sonnet ($15.00/1M tokens) is 30.0x more expensive than Grok-4.1 Fast Reasoning ($0.50/1M tokens).
In conclusion, Claude 3.7 Sonnet is more expensive than Grok-4.1 Fast Reasoning.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Grok-4.1 Fast Reasoning accepts 2,000,000 input tokens compared to Claude 3.7 Sonnet's 200,000 tokens. Claude 3.7 Sonnet can generate longer responses up to 128,000 tokens, while Grok-4.1 Fast Reasoning is limited to 30,000 tokens.
Input Capabilities
Supported data types and modalities
Both Claude 3.7 Sonnet and Grok-4.1 Fast Reasoning support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude 3.7 Sonnet
Grok-4.1 Fast Reasoning
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude 3.7 Sonnet was released on 2025-02-24, while Grok-4.1 Fast Reasoning was released on 2025-11-17.
Grok-4.1 Fast Reasoning is 9 months newer than Claude 3.7 Sonnet.
Feb 24, 2025
1.5 years ago
Nov 17, 2025
9 months ago
8mo newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
Claude 3.7 Sonnet is available from Anthropic, Bedrock, Google. Grok-4.1 Fast Reasoning is available from xAI.
Claude 3.7 Sonnet
Grok-4.1 Fast Reasoning
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude 3.7 Sonnet and Grok-4.1 Fast Reasoning side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude 3.7 Sonnet vs Grok-4.1 Fast Reasoning.