Comparisons

GPT-5.6 Luna vs Glm 4.5 Air Fp8

On provider list prices, Glm 4.5 Air Fp8 costs $0.20 per million input tokens against $0.20 for GPT-5.6 Luna: effectively level. Output is $1.10 against $1.20 (1.1x).

GPT-5.6 LunaG Glm 4.5 Air Fp8
LabOpenAIZai Org
AccessAPI onlyOpen weights
Context window1M tokens128K tokens
List price, input$0.2 / M tokens$0.2 / M tokens
List price, output$1.2 / M tokens$1.1 / M tokens
Cached input$0.02 / M tokensn/a
LicenseProprietary APIMIT
Fine-tunableNoYes

Specifications and provider list prices from the Allocate catalog, checked 2026-07-21.

What the numbers say

Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $625 a month on Glm 4.5 Air Fp8 and $660 on GPT-5.6 Luna at list: a gap of $35.

GPT-5.6 Luna reads 1M tokens per request against 128K for Glm 4.5 Air Fp8, 7.6x the window. That decides which one can take whole documents without splitting them.

GPT-5.6 Luna$0.20$1.20
Glm 4.5 Air Fp8$0.20$1.10
InputOutput

Choose GPT-5.6 Luna for

  • The longer context window (1M vs 128K tokens)
  • Published cached-input pricing ($0.02 per M tokens)
GPT-5.6 Luna details

Choose Glm 4.5 Air Fp8 for

  • Open weights you can fine-tune and own
  • Fine-tuning under a permissive license (MIT)
Glm 4.5 Air Fp8 details

Common questions

Which is cheaper, GPT-5.6 Luna or Glm 4.5 Air Fp8?

Glm 4.5 Air Fp8, on this workload shape. At list prices it is $0.20/$1.10 per million tokens in and out against $0.20/$1.20 for GPT-5.6 Luna. Billed on Allocate: $0.21/$1.18 against $0.21/$1.28.

Which has the bigger context window?

GPT-5.6 Luna: 1,000,000 tokens (1M) against 131,072 (128K) for Glm 4.5 Air Fp8.

Can I fine-tune GPT-5.6 Luna or Glm 4.5 Air Fp8?

Glm 4.5 Air Fp8 publishes open weights (MIT) and can be fine-tuned on your own data. GPT-5.6 Luna is a closed model served over API; its weights are not available.

Related comparisons

Run the numbers on your workload

Or don’t choose. On Allocate a route name is the contract: point yours at one model today, swap to the other tomorrow, and compare them on your live traffic with per-token metering.