API cost decision in 10 seconds

Llama 3 8B Lunaris vs Gemini 3.1 Pro Preview Custom Tools

Pick Llama 3 8B Lunaris for lower cost; pick Gemini 3.1 Pro Preview Custom Tools only if the larger context window matters more.

Page updated: 2026-05-26T15:08:08Z Data confirmed: 2026-05-26T19:08:13Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Llama 3 8B Lunaris for lower cost; pick Gemini 3.1 Pro Preview Custom Tools only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Llama 3 8B Lunaris is estimated at $0.07 vs $8 for Gemini 3.1 Pro Preview Custom Tools, saving $7.93 (99.2% lower).

Cost-first pickLlama 3 8B Lunaris

Context-first pickGemini 3.1 Pro Preview Custom Tools

Sample savings$7.9399.2%

10x traffic gap$79.35

Gemini 3.1 Pro Preview Custom Tools has more context, but Llama 3 8B Lunaris saves $7.93 on the standard workload. At 10x that traffic, the same price gap is about $79.35. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Llama 3 8B Lunaris stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Llama 3 8B Lunaris	Gemini 3.1 Pro Preview Custom Tools
Input-heavy / RAG	5M input + 500K output	Llama 3 8B Lunaris	$0.23	$16
Balanced workload	1M input + 1M output	Llama 3 8B Lunaris	$0.09	$14
Output-heavy chatbot	1M input + 5M output	Llama 3 8B Lunaris	$0.29	$62

Cheaper input Llama 3 8B Lunaris $0.04 vs $2 / 1M

Llama 3 8B Lunaris is $1.96 cheaper per 1M input tokens (98% lower; 50x difference).

Cheaper output Llama 3 8B Lunaris $0.05 vs $12 / 1M

Llama 3 8B Lunaris is $11.95 cheaper per 1M output tokens (99.6% lower; 240x difference).

Larger context Gemini 3.1 Pro Preview Custom Tools 8.19K vs 1.05M

Gemini 3.1 Pro Preview Custom Tools has 1.04M more context (128x larger).

Sample workload Llama 3 8B Lunaris $0.07 vs $8

Llama 3 8B Lunaris is $7.93 cheaper on the standard workload (99.2% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Llama 3 8B Lunaris Calculating… Estimated API cost

Gemini 3.1 Pro Preview Custom Tools 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

Llama 3 8B Lunaris has the lower input price; Llama 3 8B Lunaris has the lower output price; Gemini 3.1 Pro Preview Custom Tools offers the larger context window. For the 1M input plus 500K output sample, Llama 3 8B Lunaris is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.07 for Llama 3 8B Lunaris and $8 for Gemini 3.1 Pro Preview Custom Tools.

Best Fit

Choose Llama 3 8B Lunaris when you care most about lower input-token price, and lower output-token price.

Choose Gemini 3.1 Pro Preview Custom Tools when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Llama 3 8B Lunaris is estimated at $0.07 vs $8 for Gemini 3.1 Pro Preview Custom Tools, saving $7.93 (99.2% lower).
Llama 3 8B Lunaris is $7.93 cheaper on the standard workload (99.2% lower).
Llama 3 8B Lunaris is $1.96 cheaper per 1M input tokens (98% lower; 50x difference).
Llama 3 8B Lunaris is $11.95 cheaper per 1M output tokens (99.6% lower; 240x difference).
Gemini 3.1 Pro Preview Custom Tools has 1.04M more context (128x larger).

Head-to-Head Specs

Feature	Llama 3 8B Lunaris (Sao10K)	Gemini 3.1 Pro Preview Custom Tools (Google)
Input Price prompt tokens per 1M	$0.04	$2
Completion Price per 1M tokens	$0.05	$12
Sample Workload Cost 1M input + 500K output	$0.07	$8
Context Window	8.19K	1.05M
Release Date	2024-08-13	2026-02-25
Popularity	#115	#132

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Llama 3 8B Lunaris	On the standard 1M input plus 500K output workload, Llama 3 8B Lunaris is estimated at $0.07 vs $8 for Gemini 3.1 Pro Preview Custom Tools, saving $7.93 (99.2% lower).
High-volume input processing	Llama 3 8B Lunaris	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Llama 3 8B Lunaris	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Gemini 3.1 Pro Preview Custom Tools	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Gemma 4 31B (free) can replace Gemini 3.1 Pro Preview Custom Tools when lower sample workload cost matters most: $0.
Gemma 4 26B A4B (free) can replace Gemini 3.1 Pro Preview Custom Tools when lower sample workload cost matters most: $0.
Lyria 3 Clip Preview can replace Gemini 3.1 Pro Preview Custom Tools when lower sample workload cost matters most: $0.
Lyria 3 Pro Preview can replace Gemini 3.1 Pro Preview Custom Tools when lower sample workload cost matters most: $0.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
GPT-5.4 offers 1.05M context with $10 sample workload cost.

Popular competitors

DeepSeek V4 Flash · DeepSeek · #1
Hy3 preview · Tencent · #2
Claude Opus 4.7 · Anthropic · #3
Claude Sonnet 4.6 · Anthropic · #4

Cheaper alternatives

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

Open cheapest models

Larger context alternatives

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

Open largest context models

Provider catalogs

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

Open provider hubs

Sao10K catalog

Review all tracked Sao10K models before deciding whether this matchup is the right shortlist.

Open Sao10K models

Google catalog

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

Open Google models

Llama 3 8B Lunaris

Lunaris 8B is a versatile generalist and roleplaying model based on Llama 3. It's a strategic merge of multiple models, designed to balance creativity with improved logic and general knowledge....

Gemini 3.1 Pro Preview Custom Tools

Gemini 3.1 Pro Preview Custom Tools is a variant of Gemini 3.1 Pro that improves tool selection behavior by preventing overuse of a general bash tool when more efficient third-party...