Claude Opus 4.5 vs GPT-5.1 Instant: Specs & Benchmark Comparison

CharacteristicClaude Opus 4.5GPT-5.1 Instant
CompanyAnthropicOpenAI
Release DateNovember 23, 2025November 11, 2025
Parameters
MultimodalYesYes
Context (input)200K256K
Context (output)64K32K
Input Price / 1M$5.00$0.30
Output Price / 1M$25.00$1.20
Average Score0.90.9
Benchmarks
SWE-Bench Verified0.80.8
TAU2 Telecom1.01.0
GPQA0.90.9

Visual Benchmark Comparison

Claude Opus 4.5
GPT-5.1 Instant
SWE-Bench Verified0.8 vs 0.8
0.8
0.8
TAU2 Telecom1.0 vs 1.0
1.0
1.0
GPQA0.9 vs 0.9
0.9
0.9

Verdict

GPT-5.1 Instant leads in 2 out of 5 comparison categories.

Overall Performance

Both models show comparable average scores: Claude Opus 4.5 — 0.9, GPT-5.1 Instant — 0.9.

Programming

On SWE-Bench, both models are nearly equal: Claude Opus 4.5 — 0.8, GPT-5.1 Instant — 0.8.

API Cost

GPT-5.1 Instant is 20.0x cheaper: input $0.30/1M vs $5.00/1M tokens.

Context Window

GPT-5.1 Instant supports a larger context: 256K vs 200K tokens.

Recency

Both models were released around the same time: 11/23/2025 and 11/11/2025.

More About These Models

Related Comparisons

The Claude Opus 4.5 and GPT-5.1 Instant comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Opus 4.5 or GPT-5.1 Instant page. See also the complete list of AI model comparisons.