API cost decision in 10 seconds

🔥GLM 5.3 vs NewOpenAI GPT Luna Latest

Pick OpenAI GPT Luna Latest for lower cost; pick GLM 5.3 only if the larger context window matters more.

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

Budget verdict

Pick OpenAI GPT Luna Latest for lower cost; pick GLM 5.3 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, OpenAI GPT Luna Latest is estimated at $0.8 vs $3.6 for GLM 5.3, saving $2.8 (77.8% lower).

Cost-first pickOpenAI GPT Luna Latest
Context-first pickGLM 5.3
Sample savings$2.877.8%
10x traffic gap$28

GLM 5.3 has more context, but OpenAI GPT Luna Latest saves $2.8 on the standard workload. At 10x that traffic, the same price gap is about $28. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

OpenAI GPT Luna Latest stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGLM 5.3OpenAI GPT Luna Latest
Input-heavy / RAG5M input + 500K outputOpenAI GPT Luna Latest$9.2$1.6
Balanced workload1M input + 1M outputOpenAI GPT Luna Latest$5.8$1.4
Output-heavy chatbot1M input + 5M outputOpenAI GPT Luna Latest$23.4$6.2
Cheaper input OpenAI GPT Luna Latest $1.4 vs $0.2 / 1M

OpenAI GPT Luna Latest is $1.2 cheaper per 1M input tokens (85.7% lower; 7x difference).

Cheaper output OpenAI GPT Luna Latest $4.4 vs $1.2 / 1M

OpenAI GPT Luna Latest is $3.2 cheaper per 1M output tokens (72.7% lower; 3.67x difference).

Larger context GLM 5.3 1.31M vs 1.05M

GLM 5.3 has 260.72K more context (1.25x larger).

Sample workload OpenAI GPT Luna Latest $3.6 vs $0.8

OpenAI GPT Luna Latest is $2.8 cheaper on the standard workload (77.8% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GLM 5.3 Calculating… Estimated API cost
OpenAI GPT Luna Latest 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

OpenAI GPT Luna Latest has the lower input price; OpenAI GPT Luna Latest has the lower output price; GLM 5.3 offers the larger context window. For the 1M input plus 500K output sample, OpenAI GPT Luna Latest is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $3.6 for GLM 5.3 and $0.8 for OpenAI GPT Luna Latest.

Best Fit

Choose GLM 5.3 when you care most about larger context window.

Choose OpenAI GPT Luna Latest 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, OpenAI GPT Luna Latest is estimated at $0.8 vs $3.6 for GLM 5.3, saving $2.8 (77.8% lower).
  • OpenAI GPT Luna Latest is $2.8 cheaper on the standard workload (77.8% lower).
  • OpenAI GPT Luna Latest is $1.2 cheaper per 1M input tokens (85.7% lower; 7x difference).
  • OpenAI GPT Luna Latest is $3.2 cheaper per 1M output tokens (72.7% lower; 3.67x difference).
  • GLM 5.3 has 260.72K more context (1.25x larger).
Head-to-Head Specs
Feature🔥GLM 5.3
(Z.ai)		NewOpenAI GPT Luna Latest
(OpenAI)
Input Price
prompt tokens per 1M		$1.4$0.2
Completion Price
per 1M tokens		$4.4$1.2
Sample Workload Cost
1M input + 500K output		$3.6$0.8
Context Window1.31M1.05M
Release Date
Popularity#9

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionOpenAI GPT Luna LatestOn the standard 1M input plus 500K output workload, OpenAI GPT Luna Latest is estimated at $0.8 vs $3.6 for GLM 5.3, saving $2.8 (77.8% lower).
High-volume input processingOpenAI GPT Luna LatestLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsOpenAI GPT Luna LatestLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGLM 5.3A 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 5.3 when lower sample workload cost matters most: $0.
  • GLM 4.5 Air (free) can replace GLM 5.3 when lower sample workload cost matters most: $0.
  • GLM 4 32B can replace GLM 5.3 when lower sample workload cost matters most: $0.15.
  • GLM Flash Latest can replace GLM 5.3 when lower sample workload cost matters most: $0.2.
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