API cost decision in 10 seconds

NewTernary Bonsai 2 27B vs Solar Pro 4

Pick Solar Pro 4 when budget and context both matter.

Page updated: 2026-09-18T20:07:57Z Data confirmed: 2026-09-19T18:07:50Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Solar Pro 4 when budget and context both matter.

On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.27 vs $0.33 for Ternary Bonsai 2 27B, saving $0.05 (16.9% lower).

Cost-first pickSolar Pro 4

Context-first pickSolar Pro 4

Sample savings$0.0516.9%

10x traffic gap$0.55

Solar Pro 4 is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $0.55. 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 Ternary Bonsai 2 27B, balanced workload favors Solar Pro 4, and output-heavy chatbot favors Solar Pro 4.

Workload shape	Token mix	Better pick	Ternary Bonsai 2 27B	Solar Pro 4
Input-heavy / RAG	5M input + 500K output	Ternary Bonsai 2 27B	$0.62	$0.63
Balanced workload	1M input + 1M output	Solar Pro 4	$0.57	$0.45
Output-heavy chatbot	1M input + 5M output	Solar Pro 4	$2.58	$1.89

Cheaper input Ternary Bonsai 2 27B $0.075 vs $0.09 / 1M

Ternary Bonsai 2 27B is $0.01 cheaper per 1M input tokens (16.7% lower; 1.2x difference).

Cheaper output Solar Pro 4 $0.5 vs $0.36 / 1M

Solar Pro 4 is $0.14 cheaper per 1M output tokens (28% lower; 1.39x difference).

Larger context Solar Pro 4 262.14K vs 524.29K

Solar Pro 4 has 262.14K more context (2x larger).

Sample workload Solar Pro 4 $0.33 vs $0.27

Solar Pro 4 is $0.05 cheaper on the standard workload (16.9% 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 27B Calculating… Estimated API cost

Solar Pro 4 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

Ternary Bonsai 2 27B has the lower input price; Solar Pro 4 has the lower output price; Solar Pro 4 offers the larger context window. For the 1M input plus 500K output sample, Solar Pro 4 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.33 for Ternary Bonsai 2 27B and $0.27 for Solar Pro 4.

Best Fit

Choose Ternary Bonsai 2 27B when you care most about lower input-token price.

Choose Solar Pro 4 when you care most about lower output-token price, and larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.27 vs $0.33 for Ternary Bonsai 2 27B, saving $0.05 (16.9% lower).
Solar Pro 4 is $0.05 cheaper on the standard workload (16.9% lower).
Ternary Bonsai 2 27B is $0.01 cheaper per 1M input tokens (16.7% lower; 1.2x difference).
Solar Pro 4 is $0.14 cheaper per 1M output tokens (28% lower; 1.39x difference).
Solar Pro 4 has 262.14K more context (2x larger).

Head-to-Head Specs

Feature	NewTernary Bonsai 2 27B (PrismML)	Solar Pro 4 (Upstage)
Input Price prompt tokens per 1M	$0.075	$0.09
Completion Price per 1M tokens	$0.5	$0.36
Sample Workload Cost 1M input + 500K output	$0.33	$0.27
Context Window	262.14K	524.29K
Release Date	2026-09-18	2026-08-10

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Solar Pro 4	On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.27 vs $0.33 for Ternary Bonsai 2 27B, saving $0.05 (16.9% lower).
High-volume input processing	Ternary Bonsai 2 27B	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Solar Pro 4	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Solar Pro 4	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

GLM 5.3 Flash offers 1.31M context with $0.24 sample workload cost.
DeepSeek V4 Flash 0731 offers 1.31M context with $0.08 sample workload cost.
GLM Flash Latest offers 1.31M context with $0.2 sample workload cost.
DeepSeek V4 Flash Latest offers 1.31M context with $0.08 sample workload cost.

Popular competitors

Qwen3.8 Max (0902) · Qwen · #1
GPT-5.6 Luna · OpenAI · #2
DeepSeek V4.1 Flash · DeepSeek · #3
Hy4 preview · Tencent · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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PrismML catalog

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

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Upstage catalog

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

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Ternary Bonsai 2 27B

Bonsai 2 27B is a 27B-parameter reasoning model from PrismML derived from Qwen3.8-27B. It supports coding, mathematics, tool calling, and image understanding with a 262K-token context window. Ternary compression shrinks...

Solar Pro 4

Solar Pro 4 is Upstage's cost-efficient large language model, featuring a 524K context window. It is built for long-horizon tasks and agentic workflows, with strong capabilities in office productivity, document-intensive...