API cost decision in 10 seconds

Llama 3.1 8B Instruct vs GLM 4.5 Air (free)

Pick GLM 4.5 Air (free) when budget is the priority.

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

Budget verdict

Pick GLM 4.5 Air (free) when budget is the priority.

On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).

Cost-first pickGLM 4.5 Air (free)
Context-first pickBoth models
Sample savings$0.04100%
10x traffic gap$0.45

The reported context window is tied, so cost and provider fit carry more weight. 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.

GLM 4.5 Air (free) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickLlama 3.1 8B InstructGLM 4.5 Air (free)
Input-heavy / RAG5M input + 500K outputGLM 4.5 Air (free)$0.12$0
Balanced workload1M input + 1M outputGLM 4.5 Air (free)$0.07$0
Output-heavy chatbot1M input + 5M outputGLM 4.5 Air (free)$0.27$0
Cheaper input GLM 4.5 Air (free) $0.02 vs $0 / 1M

GLM 4.5 Air (free) is free for input tokens while Llama 3.1 8B Instruct costs $0.02 per 1M tokens.

Cheaper output GLM 4.5 Air (free) $0.05 vs $0 / 1M

GLM 4.5 Air (free) is free for output tokens while Llama 3.1 8B Instruct costs $0.05 per 1M tokens.

Larger context Tie 131.07K vs 131.07K

Both models report the same context window at 131.07K tokens.

Sample workload GLM 4.5 Air (free) $0.04 vs $0

GLM 4.5 Air (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
GLM 4.5 Air (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

GLM 4.5 Air (free) has the lower input price; GLM 4.5 Air (free) has the lower output price; both models report the same context window. For the 1M input plus 500K output sample, GLM 4.5 Air (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 GLM 4.5 Air (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 GLM 4.5 Air (free) when you care most about lower input-token price, and lower output-token price.

Decision Notes
  • On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).
  • GLM 4.5 Air (free) is free for the standard workload while the other model is estimated at $0.04.
  • GLM 4.5 Air (free) is free for input tokens while Llama 3.1 8B Instruct costs $0.02 per 1M tokens.
  • GLM 4.5 Air (free) is free for output tokens while Llama 3.1 8B Instruct costs $0.05 per 1M tokens.
  • Both models report the same context window at 131.07K tokens.
Head-to-Head Specs
FeatureLlama 3.1 8B Instruct
(Meta)
GLM 4.5 Air (free)
(Z.ai)
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 Window131.07K131.07K
Release Date
Popularity#40#41

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGLM 4.5 Air (free)On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.04 for Llama 3.1 8B Instruct, saving $0.04 (100% lower).
High-volume input processingGLM 4.5 Air (free)Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGLM 4.5 Air (free)Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workTieA larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

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Larger context alternatives

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Provider catalogs

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Meta catalog

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Z.ai catalog

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

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