GLM-5.2 VRAM requirements

GLM-5.2 has 753.3B parameters, of which about 40B are used per token; all 256 experts still have to be in memory. With an 8K-token context and one request it needs about 468 GB of GPU memory at Q4_K_M, 773 GB at FP8 and 1,545 GB at FP16/BF16. The published weights take 1,403 GB (BF16). No single GPU in the table holds it at Q4_K_M; it needs a multi-GPU setup.

Open GLM-5.2 in the calculator

VRAM by quantization

Weights plus the KV cache for 8,192 tokens in FP16 and the runtime overhead (0.5 GB plus 10%). Each row opens the calculator with that setting. What the GGUF names mean.

PrecisionWeightsTotalSmallest setup
As published (BF16) 1,403 GB 1,545 GB More than 8 GPUs
FP16 / BF16 1,403 GB 1,545 GB More than 8 GPUs
FP8 / INT8 702 GB 773 GB 8 × H200
INT4 (AWQ / GPTQ) 373 GB 411 GB 4 × H200
GGUF Q8_0 745 GB 821 GB 8 × H200
GGUF Q6_K 575 GB 634 GB 4 × B200
GGUF Q5_K_M 497 GB 548 GB 4 × H200
GGUF Q4_K_M 424 GB 468 GB 4 × H200
GGUF Q3_K_M 343 GB 378 GB 4 × H200
GGUF Q2_K 294 GB 324 GB 2 × B200

KV cache at long context

All 78 layers use multi-head latent attention. Each extra token of context adds 90 KB of FP16 cache per request. How the KV cache works.

ContextKV cache, FP16KV cache, FP8Total at Q4_K_M
4K tokens 362 MB 186 MB 468 GB
32K tokens 2.82 GB 1.45 GB 471 GB
128K tokens 11.3 GB 5.81 GB 480 GB
1M tokens 90.4 GB 46.5 GB 567 GB

Which GPUs can run GLM-5.2

With 8,192 tokens of context. Several GPUs means one tensor-parallel group of 2, 4 or 8 cards.

GPUMemoryQ4_K_MFP8
RTX 3060 12 GB Needs more than 8 Needs more than 8
RTX 4060 Ti 16GB 16 GB Needs more than 8 Needs more than 8
RTX 3090 / 4090 24 GB Needs more than 8 Needs more than 8
RTX 5090 32 GB Needs more than 8 Needs more than 8
A100 40GB 40 GB Needs more than 8 Needs more than 8
Mac, 64 GB unified memory about 75% of it is usable by the GPU by default 48 GB Needs more than 8 Needs more than 8
L40S / RTX 6000 Ada 48 GB Needs more than 8 Needs more than 8
A100 / H100 80GB 80 GB Needs 8 Needs more than 8
Mac, 128 GB unified memory about 75% of it is usable by the GPU by default 96 GB Needs 8 Needs more than 8
H200 141 GB Needs 4 Needs 8
B200 180 GB Needs 4 Needs 8

How fast GLM-5.2 writes

Tokens per second for one request with 8,192 tokens of context, estimated from memory bandwidth and the parameters read per token. A dash means it does not fit on one card. Try other settings in the speed calculator.

HardwareBandwidthQ4_K_MFP8
RTX 3060 12GB 360 GB/s — —
RTX 4090 1,008 GB/s — —
RTX 5090 1,792 GB/s — —
M4 Max Mac (128 GB) 546 GB/s — —
M3 Ultra Mac Studio (512 GB) 819 GB/s — —
H100 SXM 3,350 GB/s — —
H200 4,800 GB/s — —

Longest context on one GPU

How many tokens of context fit on a single card with one request and an FP16 KV cache. "Full" means the model's whole context window fits.

GPUMemoryQ4_K_MQ8_0FP8
RTX 3060 12 GB No No No
RTX 4060 Ti 16GB 16 GB No No No
RTX 3090 / 4090 24 GB No No No
RTX 5090 32 GB No No No
A100 40GB 40 GB No No No
Mac, 64 GB unified memory 48 GB No No No
L40S / RTX 6000 Ada 48 GB No No No
A100 / H100 80GB 80 GB No No No
Mac, 128 GB unified memory 96 GB No No No
H200 141 GB No No No
B200 180 GB No No No

Model details

Parameters
753.3B (753,329,940,480)
Experts
256 routed experts, all loaded
Active per token
40B (estimated from the config)
Layers
All 78 layers use multi-head latent attention
Attention cache
576 values per token (compressed latent)
Context length
1,048,576 tokens
Published weights
1,403 GB (BF16)
On Hugging Face
zai-org/GLM-5.2

Other models

Numbers read from the model files on Hugging Face on .