AllocateGLM 5.1 FP4 vs GLM 5.3
On provider list prices, GLM 5.1 FP4 costs $1.40 per million input tokens against $1.40 for GLM 5.3: effectively level. Output is $4.40 against $4.40.
Specifications and provider list prices from the Allocate catalog, checked 2026-09-12.
What the numbers say
Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $3,220 a month on GLM 5.1 FP4 and $3,220 on GLM 5.3 at list: a gap of $0.
GLM 5.3 reads 1M tokens per request against 198K for GLM 5.1 FP4, 5.2x the window. That decides which one can take whole documents without splitting them.
Common questions
Which is cheaper, GLM 5.1 FP4 or GLM 5.3?
GLM 5.1 FP4, on this workload shape. At list prices it is $1.40/$4.40 per million tokens in and out against $1.40/$4.40 for GLM 5.3. Billed on Allocate: $1.50/$4.71 against $1.50/$4.71.
Which has the bigger context window?
GLM 5.3: 1,048,575 tokens (1M) against 202,752 (198K) for GLM 5.1 FP4.
Can I fine-tune GLM 5.1 FP4 or GLM 5.3?
Both publish open weights (GLM 5.1 FP4: Not listed; GLM 5.3: Not listed), so both can be fine-tuned. On Allocate the trained weights stay inside your boundary and belong to you.
Related comparisons
Run the numbers on your workload
Or do not 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.