Claude Opus 5 vs Mercury 3
Comparing Claude Opus 5 and Mercury 3 across benchmarks, pricing, and capabilities.
Anthropic · Inception · Updated for 2026
Which is better?
Claude Opus 5 and Mercury 3 trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, Mercury 3 is roughly 61.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Opus 5
- you want predictable pricing at $5.00/M input and $25.00/M output
Choose Mercury 3
- cost matters — it's about 61.5x cheaper per token
- you want the most recent training data — it shipped Oct 2026
At a glance
The differences that matter most.
Individual benchmarks
13 reported for Claude Opus 5 · 12 for Mercury 3
Claude Opus 5 and Mercury 3don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Opus 5 ($5.00/1M tokens) is 50.0x more expensive than Mercury 3 ($0.10/1M tokens).
For output processing, Claude Opus 5 ($25.00/1M tokens) is 71.4x more expensive than Mercury 3 ($0.35/1M tokens).
In conclusion, Claude Opus 5 is more expensive than Mercury 3.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Both models have the same input context window of 1,000,000 tokens. Mercury 3 can generate longer responses up to 131,072 tokens, while Claude Opus 5 is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Claude Opus 5 supports multimodal inputs, whereas Mercury 3 does not.
Claude Opus 5 can handle both text and other forms of data like images, making it suitable for multimodal applications.
Claude Opus 5
Mercury 3
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Opus 5 was released on 2026-07-24, while Mercury 3 was released on 2026-10-19.
Mercury 3 is 3 months newer than Claude Opus 5.
Jul 24, 2026
3 months ago
Oct 19, 2026
3 days ago
2mo newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
Claude Opus 5 is available from Anthropic, DeepInfra. Mercury 3 is available from Inception.
Claude Opus 5
Mercury 3
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Opus 5 and Mercury 3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Opus 5 vs Mercury 3.