API cost decision in 10 seconds

Llama 3.1 8B Instruct vs Gemma 4 31B (free)

Pick Gemma 4 31B (free) when budget and context both matter.

Page updated:  Data confirmed:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Gemma 4 31B (free) when budget and context both matter.

On the standard 1M input plus 500K output workload, Gemma 4 31B (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).

Cost-first pickGemma 4 31B (free)
Context-first pickGemma 4 31B (free)
Sample savings$0.04100%
10x traffic gap$0.45

Gemma 4 31B (free) is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $0.45. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Gemma 4 31B (free) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickLlama 3.1 8B InstructGemma 4 31B (free)
Input-heavy / RAG5M input + 500K outputGemma 4 31B (free)$0.12$0
Balanced workload1M input + 1M outputGemma 4 31B (free)$0.07$0
Output-heavy chatbot1M input + 5M outputGemma 4 31B (free)$0.27$0
Cheaper input Gemma 4 31B (free) $0.02 vs $0 / 1M

Gemma 4 31B (free) is free for input tokens while Llama 3.1 8B Instruct costs $0.02 per 1M tokens.

Cheaper output Gemma 4 31B (free) $0.05 vs $0 / 1M

Gemma 4 31B (free) is free for output tokens while Llama 3.1 8B Instruct costs $0.05 per 1M tokens.

Larger context Gemma 4 31B (free) 131.07K vs 262.14K

Gemma 4 31B (free) has 131.07K more context (2x larger).

Sample workload Gemma 4 31B (free) $0.04 vs $0

Gemma 4 31B (free) is free for the standard workload while the other model is estimated at $0.04.

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
Llama 3.1 8B Instruct Calculating… Estimated API cost
Gemma 4 31B (free) 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

Gemma 4 31B (free) has the lower input price; Gemma 4 31B (free) has the lower output price; Gemma 4 31B (free) offers the larger context window. For the 1M input plus 500K output sample, Gemma 4 31B (free) is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.04 for Llama 3.1 8B Instruct and $0 for Gemma 4 31B (free).

Best Fit

Choose Llama 3.1 8B Instruct when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Choose Gemma 4 31B (free) when you care most about lower input-token price, lower output-token price, and larger context window.

Decision Notes
  • On the standard 1M input plus 500K output workload, Gemma 4 31B (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).
  • Gemma 4 31B (free) is free for the standard workload while the other model is estimated at $0.04.
  • Gemma 4 31B (free) is free for input tokens while Llama 3.1 8B Instruct costs $0.02 per 1M tokens.
  • Gemma 4 31B (free) is free for output tokens while Llama 3.1 8B Instruct costs $0.05 per 1M tokens.
  • Gemma 4 31B (free) has 131.07K more context (2x larger).
Head-to-Head Specs
FeatureLlama 3.1 8B Instruct
(Meta)
Gemma 4 31B (free)
(Google)
Input Price
prompt tokens per 1M
$0.02$0
Completion Price
per 1M tokens
$0.05$0
Sample Workload Cost
1M input + 500K output
$0.04$0
Context Window131.07K262.14K
Release Date
Popularity#40#105

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGemma 4 31B (free)On the standard 1M input plus 500K output workload, Gemma 4 31B (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).
High-volume input processingGemma 4 31B (free)Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGemma 4 31B (free)Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGemma 4 31B (free)A larger context window leaves more room for retrieved passages, conversation history, or source files.

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Meta catalog

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Google catalog

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