API cost decision in 10 seconds

NewGLM Flash Latest vs GPT-5.6 Luna Pro (batch)

Pick GLM Flash Latest 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 GLM Flash Latest when budget and context both matter.

On the standard 1M input plus 500K output workload, GLM Flash Latest is estimated at $0.2 vs $0.4 for GPT-5.6 Luna Pro (batch), saving $0.2 (50% lower).

Cost-first pickGLM Flash Latest
Context-first pickGLM Flash Latest
Sample savings$0.250%
10x traffic gap$2

GLM Flash Latest is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $2. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GLM Flash Latest stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGLM Flash LatestGPT-5.6 Luna Pro (batch)
Input-heavy / RAG5M input + 500K outputGLM Flash Latest$0.5$0.8
Balanced workload1M input + 1M outputGLM Flash Latest$0.33$0.7
Output-heavy chatbot1M input + 5M outputGLM Flash Latest$1.32$3.1
Cheaper input GLM Flash Latest $0.075 vs $0.1 / 1M

GLM Flash Latest is $0.03 cheaper per 1M input tokens (25% lower; 1.33x difference).

Cheaper output GLM Flash Latest $0.25 vs $0.6 / 1M

GLM Flash Latest is $0.35 cheaper per 1M output tokens (58.3% lower; 2.4x difference).

Larger context GLM Flash Latest 1.31M vs 1.05M

GLM Flash Latest has 260.72K more context (1.25x larger).

Sample workload GLM Flash Latest $0.2 vs $0.4

GLM Flash Latest is $0.2 cheaper on the standard workload (50% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GLM Flash Latest Calculating… Estimated API cost
GPT-5.6 Luna Pro (batch) 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 Flash Latest has the lower input price; GLM Flash Latest has the lower output price; GLM Flash Latest offers the larger context window. For the 1M input plus 500K output sample, GLM Flash Latest is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.2 for GLM Flash Latest and $0.4 for GPT-5.6 Luna Pro (batch).

Best Fit

Choose GLM Flash Latest when you care most about lower input-token price, lower output-token price, and larger context window.

Choose GPT-5.6 Luna Pro (batch) when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Decision Notes
  • On the standard 1M input plus 500K output workload, GLM Flash Latest is estimated at $0.2 vs $0.4 for GPT-5.6 Luna Pro (batch), saving $0.2 (50% lower).
  • GLM Flash Latest is $0.2 cheaper on the standard workload (50% lower).
  • GLM Flash Latest is $0.03 cheaper per 1M input tokens (25% lower; 1.33x difference).
  • GLM Flash Latest is $0.35 cheaper per 1M output tokens (58.3% lower; 2.4x difference).
  • GLM Flash Latest has 260.72K more context (1.25x larger).
Head-to-Head Specs
FeatureNewGLM Flash Latest
(Z.ai)		GPT-5.6 Luna Pro (batch)
(OpenAI)
Input Price
prompt tokens per 1M		$0.075$0.1
Completion Price
per 1M tokens		$0.25$0.6
Sample Workload Cost
1M input + 500K output		$0.2$0.4
Context Window1.31M1.05M
Release Date

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGLM Flash LatestOn the standard 1M input plus 500K output workload, GLM Flash Latest is estimated at $0.2 vs $0.4 for GPT-5.6 Luna Pro (batch), saving $0.2 (50% lower).
High-volume input processingGLM Flash LatestLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGLM Flash LatestLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGLM Flash LatestA larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps
  • GLM 5.2 (free) can replace GLM Flash Latest when lower sample workload cost matters most: $0.
  • GLM 4.5 Air (free) can replace GLM Flash Latest when lower sample workload cost matters most: $0.
  • GLM 4 32B can replace GLM Flash Latest when lower sample workload cost matters most: $0.15.
  • gpt-oss-120b (free) can replace GPT-5.6 Luna Pro (batch) when lower sample workload cost matters most: $0.
Larger context near this budget
  • No larger-context model is currently tracked within a close sample-cost band.

Cheaper alternatives

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

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Larger context alternatives

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Provider catalogs

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Z.ai catalog

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OpenAI catalog

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GLM Flash Latest

This model always redirects to the latest model in the GLM Flash family.

GPT-5.6 Luna Pro (batch)

GPT-5.6 Luna Pro is the same underlying model as [GPT-5.6 Luna](https://openrouter.ai/openai/gpt-5.6-luna), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode