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Models · claude

Claude 3 Opus

Proprietary Anthropic · 2024-03-04 · Proprietary

The flagship of the Claude 3 family at launch, marketed as Anthropic's most capable model with vision input and a 200K context window. Set the price ceiling for closed frontier chat at $15 input / $75 output per million tokens, a tier matched by GPT-4 Turbo at the time.

Cost

$15.00 / Mtok input
$75.00 / Mtok output

Anthropic API · as of 2026-05-21

source ↗

Speed

0 tok/sec output
0 ms TTFT

· as of 2026-05-21

source ↗

Architecture

tokens in Embedding vocab not disclosed × N layers Architecture not disclosed (proprietary or undocumented) Output projection tokens out
Schema-generated from data/models.yaml. Every label is auditable against the model's sources.

Specs

Architecture
unknown
Total params
not disclosed
Active params
not disclosed
Context window
200K tokens
Attention
unknown
Position encoding
unknown
Post-training
rlhf, constitutional
OSI-approved
no
Data released
no
Training code
not released

Benchmarks

Each score carries the date it was published; we never infer or interpolate missing scores.

General reasoning

MMLU-Pro 69.6 as of 2026-05-21 source ↗
GPQA-Diamond 48.9 as of 2026-05-21 source ↗

Code

LiveCodeBench 27.9 as of 2026-05-21 source ↗

Math

MATH 64.1 as of 2026-05-21 source ↗
AIME 2024 3.3 as of 2026-05-21 source ↗

Available quantizations

None. The weights are not distributed, so there are no public quantizations.

Notable innovations

  • · 200K context window across the family
  • · Vision input on every Claude 3 variant
  • · Near-perfect Needle-in-a-Haystack recall (>99%)

Lineage

Predecessor flagship Opus; the Claude 4 line returned to the Opus name after skipping a 3.5 Opus.

Derivatives

Sources