API cost decision in 10 seconds

NewMercury 2.5 vs Claude Opus 4.8

Pick Mercury 2.5 for lower cost; pick Claude Opus 4.8 only if the larger context window matters more.

Page updated: 2026-09-08T19:08:22Z Data confirmed: 2026-09-08T19:08:22Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Mercury 2.5 for lower cost; pick Claude Opus 4.8 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Mercury 2.5 is estimated at $0.11 vs $17.5 for Claude Opus 4.8, saving $17.39 (99.3% lower).

Cost-first pickMercury 2.5

Context-first pickClaude Opus 4.8

Sample savings$17.3999.3%

10x traffic gap$173.85

Claude Opus 4.8 has more context, but Mercury 2.5 saves $17.39 on the standard workload. At 10x that traffic, the same price gap is about $173.85. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Mercury 2.5 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Mercury 2.5	Claude Opus 4.8
Input-heavy / RAG	5M input + 500K output	Mercury 2.5	$0.28	$37.5
Balanced workload	1M input + 1M output	Mercury 2.5	$0.19	$30
Output-heavy chatbot	1M input + 5M output	Mercury 2.5	$0.79	$130

Cheaper input Mercury 2.5 $0.04 vs $5 / 1M

Mercury 2.5 is $4.96 cheaper per 1M input tokens (99.2% lower; 125x difference).

Cheaper output Mercury 2.5 $0.15 vs $25 / 1M

Mercury 2.5 is $24.85 cheaper per 1M output tokens (99.4% lower; 166.7x difference).

Larger context Claude Opus 4.8 260K vs 1M

Claude Opus 4.8 has 740K more context (3.85x larger).

Sample workload Mercury 2.5 $0.11 vs $17.5

Mercury 2.5 is $17.39 cheaper on the standard workload (99.3% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Mercury 2.5 Calculating… Estimated API cost

Claude Opus 4.8 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 2.5 has the lower input price; Mercury 2.5 has the lower output price; Claude Opus 4.8 offers the larger context window. For the 1M input plus 500K output sample, Mercury 2.5 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.11 for Mercury 2.5 and $17.5 for Claude Opus 4.8.

Best Fit

Choose Mercury 2.5 when you care most about lower input-token price, and lower output-token price.

Choose Claude Opus 4.8 when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Mercury 2.5 is estimated at $0.11 vs $17.5 for Claude Opus 4.8, saving $17.39 (99.3% lower).
Mercury 2.5 is $17.39 cheaper on the standard workload (99.3% lower).
Mercury 2.5 is $4.96 cheaper per 1M input tokens (99.2% lower; 125x difference).
Mercury 2.5 is $24.85 cheaper per 1M output tokens (99.4% lower; 166.7x difference).
Claude Opus 4.8 has 740K more context (3.85x larger).

Head-to-Head Specs

Feature	NewMercury 2.5 (Inception)	Claude Opus 4.8 (Anthropic)
Input Price prompt tokens per 1M	$0.04	$5
Completion Price per 1M tokens	$0.15	$25
Sample Workload Cost 1M input + 500K output	$0.11	$17.5
Context Window	260K	1M
Release Date	2026-09-08	2026-05-27

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Mercury 2.5	On the standard 1M input plus 500K output workload, Mercury 2.5 is estimated at $0.11 vs $17.5 for Claude Opus 4.8, saving $17.39 (99.3% lower).
High-volume input processing	Mercury 2.5	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Mercury 2.5	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Claude Opus 4.8	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 4.8 when lower sample workload cost matters most: $0.88.
Claude Haiku 4.5 (batch) can replace Claude Opus 4.8 when lower sample workload cost matters most: $1.75.
Claude 3.5 Haiku can replace Claude Opus 4.8 when lower sample workload cost matters most: $2.8.
Claude Sonnet 5 (batch) can replace Claude Opus 4.8 when lower sample workload cost matters most: $3.5.

Larger context near this budget

Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
DeepSeek V4 Flash 0731 offers 1.31M context with $0.15 sample workload cost.
GLM 5.3 Flash offers 1.31M context with $0.2 sample workload cost.

Popular competitors

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GPT-5.6 Luna · OpenAI · #2
DeepSeek V4 Flash 0731 · DeepSeek · #3
GLM 5.3 Flash · Z.ai · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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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.

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Mercury 2.5

Mercury 2.5 is the fastest reasoning LLM, and the latest diffusion LLM (dLLM) from Inception. Instead of generating tokens sequentially, Mercury 2.5 produces and refines multiple tokens in parallel, achieving...

Claude Opus 4.8

Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token...