When was Claude 3 Opus released?

Claude 3 Opus was released by Anthropic on Monday, Mar 4 2024.

Who made Claude 3 Opus?

Claude 3 Opus was built by Anthropic. AI safety company building the Claude family of models. Founded in 2021 by former OpenAI researchers.

What benchmark scores did Claude 3 Opus get?

Claude 3 Opus reports 2 tracked benchmark scores — SWE-Bench Verified: 33%; GPQA Diamond: 50.4%. Tracked scores may come from lab reports or independent benchmarks; source details accompany the benchmark data.

What is the context window of Claude 3 Opus?

Claude 3 Opus has a context window of 200k. That is the maximum amount of input plus output the model can hold in a single request.

Is Claude 3 Opus open source?

No. Claude 3 Opus is a closed model. The weights are not published — it is available only through the provider's own API, apps, or partner platforms.

What came before and after Claude 3 Opus?

Anthropic's previous tracked release was Claude 3 Sonnet on Mar 4 2024. It was followed by Claude 3.5 Sonnet on Jun 20 2024.

Claude 3 Opus

Released Mar 4 2024

Claude 3 Opus is an AI model released by Anthropic on Monday, Mar 4 2024, the same day as Claude 3 Sonnet. It has a 200k token context window. Benchmark results (shown below) cover SWE-Bench Verified, and GPQA Diamond.

Benchmarks

Coding

SWE-Bench Verified

33%

#65 of 70

Reasoning & science

GPQA Diamond

50.4%

#58 of 66

Compare Claude 3 Opus with

Claude 3 Opus

Suggested comparisons

Claude 3 OpusvsClaude Haiku 5.5 Claude 3 OpusvsGPT-6.1 Sol Claude 3 OpusvsGemini 4 Argon Claude 3 OpusvsMuse Spark Open Claude 3 OpusvsGrok 4.7 Claude 3 OpusvsDeepSeek-V4.1-Flash-1017 Claude 3 OpusvsMistral Large 4 Claude 3 OpusvsKimi K3 Claude 3 OpusvsGLM-5.3-Flash Claude 3 OpusvsQwen3.8-Max-0902 Claude 3 OpusvsNemotron 3.5 Super VL

About

Claude 3 Opus was the flagship of the Claude 3 family, launched on March 4, 2024 alongside the faster Claude 3 Sonnet and Claude 3 Haiku. It was the first Claude generation with vision support, shipped with a 200K-token context window, and outperformed GPT-4 on a wide range of benchmarks at launch — a moment that established Anthropic as a genuine frontier-lab rival rather than a safety-focused also-ran.

Opus was marketed on graduate-level reasoning: it scored 50.4% on GPQA Diamond and 33.0% on SWE-Bench Verified, both leading numbers for early 2024. It remained Anthropic's largest model for over a year, until the Claude 4 generation arrived in May 2025, and its three-tier Haiku/Sonnet/Opus naming scheme still structures the Claude lineup today.

Frequently asked questions

: Claude 3 Opus was released by Anthropic on Monday, Mar 4 2024.
: Claude 3 Opus was built by Anthropic. AI safety company building the Claude family of models. Founded in 2021 by former OpenAI researchers.
: Claude 3 Opus reports 2 tracked benchmark scores — SWE-Bench Verified: 33%; GPQA Diamond: 50.4%. Tracked scores may come from lab reports or independent benchmarks; source details accompany the benchmark data.
: Claude 3 Opus has a context window of 200k. That is the maximum amount of input plus output the model can hold in a single request.
: No. Claude 3 Opus is a closed model. The weights are not published — it is available only through the provider's own API, apps, or partner platforms.
: Anthropic's previous tracked release was Claude 3 Sonnet on Mar 4 2024. It was followed by Claude 3.5 Sonnet on Jun 20 2024.