Last verified 2025-11-26 (left) · 2025-11-26 (right)
GPT-5.1 vs Grok 4.1 — Pricing & Capability Comparison
GPT-5.1 charges $1.25 per million input tokens and $10.00 per million output tokens. Grok 4.1 comes in at $0.20 / $0.50. Context windows span 200K vs 2M tokens respectively.
TL;DR — Quick Comparison
- ✓Grok 4.1 is cheaper overall: $0.70 per 1M tokens (in+out) vs $11.25 for GPT-5.1 — saves $10.55 per 1M tokens
- ✓Input pricing: GPT-5.1 $1.25/1M vs Grok 4.1 $0.20/1M
- ✓Output pricing: GPT-5.1 $10.00/1M vs Grok 4.1 $0.50/1M
- ✓Context window: Grok 4.1 offers more (2M vs 200K)
- ✓Use our calculator below to estimate costs for your specific usage pattern
Input price (per 1M)
GPT-5.1
$1.25
Grok 4.1
$0.20
Grok 4.1 leads here
Output price (per 1M)
GPT-5.1
$10.00
Grok 4.1
$0.50
Grok 4.1 leads here
Context window
GPT-5.1
200,000 tokens
Grok 4.1
2,000,000 tokens
Grok 4.1 leads here
Cached input
GPT-5.1
$0.125
Grok 4.1
$0.050
Grok 4.1 leads here
Cost comparison for 10K-token workloads
Side-by-side pricing for identical workloads (10,000 total tokens per request) across different distributions.
| Scenario | GPT-5.1 | Grok 4.1 | GPT-5.1 cached | Grok 4.1 cached |
|---|---|---|---|---|
Balanced conversation 50% input · 50% output | $0.0563 | $0.0035 | $0.0506 | $0.0027 |
Input-heavy workflow 80% input · 20% output | $0.0300 | $0.0026 | $0.0210 | $0.0014 |
Generation heavy 30% input · 70% output | $0.0738 | $0.0041 | $0.0704 | $0.0037 |
Cached system prompt 90% cached input · 10% fresh output | $0.0212 | $0.0023 | $0.0111 | $0.0009 |
Frequently asked questions
Which is cheaper: GPT-5.1 or Grok 4.1?
Grok 4.1 is cheaper for input tokens at $0.20 per 1M tokens compared to $1.25. For output, Grok 4.1 costs $0.50 per 1M tokens versus $10.00 for GPT-5.1.
What is the cost per 1M tokens for GPT-5.1?
GPT-5.1 pricing: $1.25 per 1M input tokens and $10.00 per 1M output tokens. Context window: 200,000 tokens.
What is the cost per 1M tokens for Grok 4.1?
Grok 4.1 pricing: $0.20 per 1M input tokens and $0.50 per 1M output tokens. Context window: 2,000,000 tokens.
How much does it cost per 1K tokens?
Per 1K tokens: GPT-5.1 costs $0.0013 input / $0.0100 output. Grok 4.1 costs $0.0002 input / $0.0005 output. This is useful for calculating small-scale usage costs.
Which model supports a larger context window?
Grok 4.1 offers 2,000,000 tokens (2M) versus 200K for GPT-5.1.
What is the estimated monthly cost for typical usage?
For a typical workload of 10M input + 2M output tokens per month: GPT-5.1 would cost approximately $32.50, while Grok 4.1 would cost $3.00. Grok 4.1 is more economical for this usage pattern.
Do these models support prompt caching?
GPT-5.1 supports prompt caching at $0.125 per 1M cached tokens, reducing costs for repeated context by up to 90%. Grok 4.1 supports caching at $0.050 per 1M tokens, saving up to 75%.
Which model is best for my use case?
Choose Grok 4.1 for cost-sensitive applications with high input volume. Choose Grok 4.1 if you need 2M context for long documents or conversations. Consider prompt caching if you have repeated context. Use our token calculator to model your specific usage pattern.