claude-opus-5 vs gpt-5.1
Side-by-side comparison of claude-opus-5 and gpt-5.1: benchmarks, pricing, context window and capabilities. Both are accessible through Requesty's unified API. claude-opus-5 outperforms gpt-5.1 on 4 of 4 shared benchmarks.
claude-opus-5
Input / 1M
$5.00
Output / 1M
$25.00
Context
1M
Model ID
anthropic/claude-opus-5
gpt-5.1
Input / 1M
$1.25
Output / 1M
$10.00
Context
400K
Model ID
openai/gpt-5.1
Benchmark comparison
Intelligence Indexreasoning
claude-opus-554.1%
gpt-5.129.1%
Coding Indexcoding
claude-opus-578.0%
gpt-5.149.4%
Math Indexmath
claude-opus-5N/A
gpt-5.194.0%
GPQA Diamondreasoning
claude-opus-593.2%
gpt-5.187.3%
AIME 2025math
claude-opus-5N/A
gpt-5.194.0%
LiveCodeBenchcoding
claude-opus-5N/A
gpt-5.186.8%
Terminal-Bench Hardagentic
claude-opus-5N/A
gpt-5.145.5%
τ²-Benchagentic
claude-opus-5N/A
gpt-5.181.9%
SciCodecoding
claude-opus-556.4%
gpt-5.1N/A
MMLU Proknowledge
claude-opus-5N/A
gpt-5.187.0%
Humanity's Last Examreasoning
claude-opus-554.9%
gpt-5.128.5%
Scores sourced from official model cards, Artificial Analysis, and public leaderboards. Benchmarks measure specific skills and don't capture every aspect of model quality.
Pricing & specifications
| claude-opus-5 | gpt-5.1 | |
|---|---|---|
| Input price / 1M | $5.00 | $1.25 |
| Output price / 1M | $25.00 | $10.00 |
| Context window | 1M tokens | 400K tokens |
| Max output | 128K tokens | 128K tokens |
| Vision input | Yes | Yes |
| Tool calling | Yes | Yes |
| Reasoning | Yes | Yes |
| Prompt caching | Yes | Yes |
| Computer use | Yes | N/A |
| Provider | Anthropic PBC | OpenAI Inc. |
Questions people ask
Is claude-opus-5 better than gpt-5.1?
claude-opus-5 outperforms gpt-5.1 on 4 of 4 shared benchmarks. See the benchmark comparison above for specifics: claude-opus-5 and gpt-5.1 have different strengths across reasoning, coding, math and multimodal tasks.
Which is cheaper, claude-opus-5 or gpt-5.1?
gpt-5.1 is cheaper. claude-opus-5 costs $5.00/$25.00 per 1M input/output tokens, while gpt-5.1 costs $1.25/$10.00.
Can I use claude-opus-5 and gpt-5.1 through the same API?
Yes. Requesty provides a single OpenAI-compatible API that routes to both. Change just the "model" parameter to switch between "anthropic/claude-opus-5" and "openai/gpt-5.1", no other code changes needed.
What are the context windows?
claude-opus-5 supports up to 1M tokens of context. gpt-5.1 supports up to 400K tokens. Longer context means you can feed larger documents or codebases in a single prompt, though quality often degrades past 128K for most models.
Switch between claude-opus-5 and gpt-5.1 with one line of code
Requesty provides a single OpenAI-compatible API for 600+ models. Change the model parameter, not your code.