API cost decision in 10 seconds

NewTernary Bonsai 2 9B vs Mercury 2.5

Pick Mercury 2.5 for lower cost; pick Ternary Bonsai 2 9B only if the larger context window matters more.

Page updated: 2026-10-27T20:08:11Z Data confirmed: 2026-10-28T05:08:04Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Mercury 2.5 for lower cost; pick Ternary Bonsai 2 9B 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 $0.15 for Ternary Bonsai 2 9B, saving $0.03 (20.7% lower).

Cost-first pickMercury 2.5

Context-first pickTernary Bonsai 2 9B

Sample savings$0.0320.7%

10x traffic gap$0.3

Ternary Bonsai 2 9B has more context, but Mercury 2.5 saves $0.03 on the standard workload. At 10x that traffic, the same price gap is about $0.3. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Cost winner changes by workload shape: input-heavy / RAG favors Mercury 2.5, balanced workload favors Mercury 2.5, and output-heavy chatbot favors Ternary Bonsai 2 9B.

Workload shape	Token mix	Better pick	Ternary Bonsai 2 9B	Mercury 2.5
Input-heavy / RAG	5M input + 500K output	Mercury 2.5	$0.47	$0.28
Balanced workload	1M input + 1M output	Mercury 2.5	$0.21	$0.19
Output-heavy chatbot	1M input + 5M output	Ternary Bonsai 2 9B	$0.73	$0.79

Cheaper input Mercury 2.5 $0.08 vs $0.04 / 1M

Mercury 2.5 is $0.04 cheaper per 1M input tokens (50% lower; 2x difference).

Cheaper output Ternary Bonsai 2 9B $0.13 vs $0.15 / 1M

Ternary Bonsai 2 9B is $0.02 cheaper per 1M output tokens (13.3% lower; 1.15x difference).

Larger context Ternary Bonsai 2 9B 262.14K vs 260K

Ternary Bonsai 2 9B has 2.14K more context (1.01x larger).

Sample workload Mercury 2.5 $0.15 vs $0.11

Mercury 2.5 is $0.03 cheaper on the standard workload (20.7% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Ternary Bonsai 2 9B Calculating… Estimated API cost

Mercury 2.5 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 2.5 has the lower input price; Ternary Bonsai 2 9B has the lower output price; Ternary Bonsai 2 9B 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 $0.15 for Ternary Bonsai 2 9B and $0.11 for Mercury 2.5.

Best Fit

Choose Ternary Bonsai 2 9B when you care most about lower output-token price, and larger context window.

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

Decision Notes

On the standard 1M input plus 500K output workload, Mercury 2.5 is estimated at $0.11 vs $0.15 for Ternary Bonsai 2 9B, saving $0.03 (20.7% lower).
Mercury 2.5 is $0.03 cheaper on the standard workload (20.7% lower).
Mercury 2.5 is $0.04 cheaper per 1M input tokens (50% lower; 2x difference).
Ternary Bonsai 2 9B is $0.02 cheaper per 1M output tokens (13.3% lower; 1.15x difference).
Ternary Bonsai 2 9B has 2.14K more context (1.01x larger).

Head-to-Head Specs

Feature	NewTernary Bonsai 2 9B (PrismML)	Mercury 2.5 (Inception)
Input Price prompt tokens per 1M	$0.08	$0.04
Completion Price per 1M tokens	$0.13	$0.15
Sample Workload Cost 1M input + 500K output	$0.15	$0.11
Context Window	262.14K	260K
Release Date	2026-10-16	2026-09-08

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 $0.15 for Ternary Bonsai 2 9B, saving $0.03 (20.7% 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	Ternary Bonsai 2 9B	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Ternary Bonsai 2 9B	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

No lower-cost same-provider swap is currently tracked for this pair.

Larger context near this budget

GPT-6 Luna Pro (batch) offers 1.05M context with $0.17 sample workload cost.
GPT-6 Luna (batch) offers 1.05M context with $0.17 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.
GLM 5.3 Flash offers 1.05M context with $0.08 sample workload cost.

Popular competitors

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Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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

Open provider hubs

PrismML catalog

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

Open PrismML models

Inception catalog

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

Open Inception models

Ternary Bonsai 2 9B

Ternary Bonsai 2 9B is PrismML’s compact, open-weight language model for conversational AI, reasoning, and tool use. Built on Qwen3.5, it uses ternary weights packed into 2 bits for efficient...

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...