Zhipu AI
GLM 5.2 (400B)
Zhipu AI's open-weight frontier model for reasoning and coding
Model Summary
Family
GLM
Version
5.2
Parameters
400B (est.)
Parameter counts for closed models are estimates; vendors rarely publish exact sizes.
VRAM Requirements by Quantization
Memory needed to serve GLM 5.2 (400B) for inference, including a 20% overhead for activations and KV cache.
| Precision | VRAM needed | Smallest single GPU that fits |
|---|---|---|
| INT4 (4-bit) | 223.52 GB | AMD Instinct MI325X (256 GB) |
| INT8 (8-bit) | 447.03 GB | Multi-GPU required |
| FP16 (16-bit) | 894.07 GB | Multi-GPU required |
| FP32 (32-bit) | 1788.14 GB | Multi-GPU required |
Recommended GPU Configurations
Cheapest on-demand configurations to serve GLM 5.2 (400B) at 8-bit (447 GB VRAM).
2x AMD Instinct MI325X
512 GB total VRAM · CDNA 3
~$16.00/h
3x AMD Instinct MI300X
576 GB total VRAM · CDNA 3
~$18.00/h
2x AMD Instinct MI355X
576 GB total VRAM · CDNA 4
~$26.00/h
Quick GPU Planning
Use the calculator pre-filled with this exact version to estimate memory, speed, and compute requirements in a few clicks.
Access Pre-filled CalculatorFrequently Asked Questions
How much VRAM do you need to run GLM 5.2 (400B)?
With an estimated 400B parameters, GLM 5.2 (400B) needs roughly 447 GB of VRAM in 8-bit (INT8), 224 GB in 4-bit, and 894 GB in FP16, including a 20% overhead for activations and KV cache.
Which GPUs can run GLM 5.2 (400B)?
At 8-bit quantization, the most cost-effective option is 2x AMD Instinct MI325X (512 GB combined VRAM, around $16.00/hour on-demand). Higher-end cards like the NVIDIA B200 or AMD MI355X reduce the GPU count needed.
Can GLM 5.2 (400B) run on a single GPU?
Only with aggressive quantization: in 4-bit, a single AMD Instinct MI325X (256 GB) can fit it. At 8-bit or higher, you need a multi-GPU setup.
How much does it cost to serve GLM 5.2 (400B) in the cloud?
Renting 2x Instinct MI325X costs on the order of $16.00/hour, i.e. about $11,680/month running 24/7. Actual prices vary by provider and commitment; spot and reserved capacity can be significantly cheaper.
Deploy on a GPU cloud
Rent 2x Instinct MI325X by the hour instead of buying hardware.
