API cost decision in 10 seconds

Mercury 2 vs Claude Opus 4.5

Pick Mercury 2 for lower cost; pick Claude Opus 4.5 only if the larger context window matters more.

Pricing data updated: 2026-05-26T11:08:00Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Mercury 2 for lower cost; pick Claude Opus 4.5 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $17.5 for Claude Opus 4.5, saving $16.88 (96.4% lower).

Cost-first pickMercury 2

Context-first pickClaude Opus 4.5

Sample savings$16.8896.4%

10x traffic gap$168.75

Claude Opus 4.5 has more context, but Mercury 2 saves $16.88 on the standard workload. At 10x that traffic, the same price gap is about $168.75. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Mercury 2 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Mercury 2	Claude Opus 4.5
Input-heavy / RAG	5M input + 500K output	Mercury 2	$1.62	$37.5
Balanced workload	1M input + 1M output	Mercury 2	$1	$30
Output-heavy chatbot	1M input + 5M output	Mercury 2	$4	$130

Cheaper input Mercury 2 $0.25 vs $5 / 1M

Mercury 2 is $4.75 cheaper per 1M input tokens (95% lower; 20x difference).

Cheaper output Mercury 2 $0.75 vs $25 / 1M

Mercury 2 is $24.25 cheaper per 1M output tokens (97% lower; 33.3x difference).

Larger context Claude Opus 4.5 128K vs 200K

Claude Opus 4.5 has 72K more context (1.56x larger).

Sample workload Mercury 2 $0.62 vs $17.5

Mercury 2 is $16.88 cheaper on the standard workload (96.4% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Mercury 2 Calculating… Estimated API cost

Claude Opus 4.5 Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

Mercury 2 has the lower input price; Mercury 2 has the lower output price; Claude Opus 4.5 offers the larger context window. For the 1M input plus 500K output sample, Mercury 2 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.62 for Mercury 2 and $17.5 for Claude Opus 4.5.

Best Fit

Choose Mercury 2 when you care most about lower input-token price, and lower output-token price.

Choose Claude Opus 4.5 when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $17.5 for Claude Opus 4.5, saving $16.88 (96.4% lower).
Mercury 2 is $16.88 cheaper on the standard workload (96.4% lower).
Mercury 2 is $4.75 cheaper per 1M input tokens (95% lower; 20x difference).
Mercury 2 is $24.25 cheaper per 1M output tokens (97% lower; 33.3x difference).
Claude Opus 4.5 has 72K more context (1.56x larger).

Head-to-Head Specs

Feature	Mercury 2 (Inception)	Claude Opus 4.5 (Anthropic)
Input Price prompt tokens per 1M	$0.25	$5
Completion Price per 1M tokens	$0.75	$25
Sample Workload Cost 1M input + 500K output	$0.62	$17.5
Context Window	128K	200K
Release Date	2026-03-04	2025-11-24

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Mercury 2	On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $17.5 for Claude Opus 4.5, saving $16.88 (96.4% lower).
High-volume input processing	Mercury 2	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Mercury 2	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Claude Opus 4.5	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Claude 3 Haiku can replace Claude Opus 4.5 when lower sample workload cost matters most: $0.88.
Claude 3.5 Haiku can replace Claude Opus 4.5 when lower sample workload cost matters most: $2.8.
Anthropic Claude Haiku Latest can replace Claude Opus 4.5 when lower sample workload cost matters most: $3.5.
Claude Haiku 4.5 can replace Claude Opus 4.5 when lower sample workload cost matters most: $3.5.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
OpenAI GPT Latest offers 1.05M context with $20 sample workload cost.

Popular competitors

No popular competitor is currently available.

Cheaper alternatives

Review low-cost models sorted by a standard 1M input plus 500K output workload.

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Larger context alternatives

Find models with larger context windows for RAG, long documents, and codebase review.

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Provider catalogs

Compare models within provider hubs before choosing a final API vendor.

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Inception catalog

Review all tracked Inception models before deciding whether this matchup is the right shortlist.

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Anthropic catalog

Check other Anthropic models with comparable pricing, context, or release timing.

Open Anthropic models

Mercury 2

Mercury 2 is an extremely fast reasoning LLM, and the first reasoning diffusion LLM (dLLM). Instead of generating tokens sequentially, Mercury 2 produces and refines multiple tokens in parallel, achieving...

Claude Opus 4.5

Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and...