Llama 3.1 405B Instruct vs GLM 5.3 Flash
GLM 5.3 Flash leads llmrun Score 124.1 to 83.5; neither fits 24 GB.
Run GLM 5.3 Flash in the cloud →
Model A · Meta
Llama 3.1 405B Instruct405.9B · Llama 3.1 Community · Jul 2024
Model B · Z.ai
GLM 5.3 Flash321.3B · 18.3B active · 1M context · MIT · Aug 2026
Choose Llama 3.1 405B Instruct if you want…
Also does chat
GLM 5.3 Flash doesn't list it
Choose GLM 5.3 Flash if you want…
Higher llmrun Score
124.1 vs 83.5
Stronger at reasoning
127.4 vs 86.4
Stronger at science
123.5 vs 84.6
Ahead on the benchmarks
3 of 3 shared boards
Lighter on memory
194.6 vs 267.9 GB at Q4_K_M
Also does vision
Llama 3.1 405B Instruct doesn't list it
On your hardware
Each model at its default quant (Q4_K_M), a smaller one when it must. Estimates, ±20%.
8 GB
RTX 4060 · 8 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
12 GB
RTX 3060 12GB · 12 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
16 GB
RTX 5060 Ti 16GB · 16 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
24 GBreference
RTX 4090 · 24 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
32 GB
RTX 5090 · 32 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
48 GB
RTX A6000 · 48 GB tier
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
Mac 32 GB
Mac Mini M4 · Macs
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
Mac 64 GB
Mac Studio M4 Max · Macs
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
Doesn't fit
smallest quant needs 100.7 GB
Mac 128 GB
Mac Studio M4 Max · Macs
Llama 3.1 405B Instruct
Doesn't fit
smallest quant needs 197.4 GB
GLM 5.3 Flash
IQ2_S · ~41 tok/s
112.8 GB · up to 16Kfits
Reference GPU: RTX 4090. Tinted cell = the better pick on that machine (fits, more headroom, or at least 10% faster).
Overall
Llama 3.1 405B Instruct
GLM 5.3 Flash
Coding
Llama 3.1 405B Instruct
no data
GLM 5.3 Flash
Agents
Llama 3.1 405B Instruct
no data
GLM 5.3 Flash
Math
Llama 3.1 405B Instruct
no data
GLM 5.3 Flash
Science
Llama 3.1 405B Instruct
GLM 5.3 Flash
Reasoning
Llama 3.1 405B Instruct
GLM 5.3 Flash
Llama 3.1 405B Instruct · #82 of 106 open models · #78 of 102 that fit ≤512 GB
GLM 5.3 Flash · #12 of 106 open models · #6 of 89 that fit ≤256 GB
Benchmarks
3 shared boards: Llama 3.1 405B Instruct leads 0, GLM 5.3 Flash leads 3 · Benchmarks imported Nov 2026
Llama 3.1 405B Instruct
50.9%#55/100 open
IndependentEpoch AI · Jul 2024
GLM 5.3 Flash
90.1%#11/100 open
IndependentEpoch AI · Aug 2026
Llama 3.1 405B Instruct
9.7%#60/88 open
IndependentEpoch AI · Jul 2024
GLM 5.3 Flash
93.9%#11/88 open
IndependentEpoch AI · Aug 2026
Llama 3.1 405B Instruct
0.0%#63/84 open
Lab-reportedEpoch AI · Jul 2024
GLM 5.3 Flash
15.4%#10/84 open
Lab-reportedEpoch AI · Aug 2026
36 more boards (other shared and single-model boards)
Llama 3.1 405B Instruct
1335.5#87/188 open
ArenaLMArena · Oct 2026
GLM 5.3 Flash
1476.5#4/188 open
ArenaLMArena · Oct 2026
Only Llama 3.1 405B Instruct (8)
- MMLU-Pro73.3%
- SimpleBench23.0%
- MATH Level 549.8%
- MMLU84.5%
- WeirdML21.4%
- DTBench61.4%
- ForecastBench62.6
- WinoGrande82.2%
Only GLM 5.3 Flash (27)
- LiveBench Coding79.0
- LiveBench Reasoning77.6
- FrontierMath55.8%
- LMArena WebDev1606.6
- LiveBench Math81.2
- ARC-AGI-265.8%
- SciCode51.6%
- ARC-AGI91.0%
- FrontierMath Tier 417.1%
- DeepSWE63.4%
- FrontierCode31.8%
- APEX-Agents52.8%
- Chess Puzzles21.0%
- LiveBench 2026 Reasoning77.6
- Mystery Game Puzzles8.0%
- GDP.pdf14.0%
- LiveBench 2026 Browser84.0
- LiveBench 2026 Data Analysis76.4
- ALE-Bench303.6
- CursorBench36.8%
- FrontierSWE18.1%
- LiveBench 2026 Coding80.6
- LiveBench 2026 Long-Horizon28.4
- Surface Evolver Bench52.5%
- LiveBench 2026 Design77.2
- ProofBench21.0%
- LiveBench 2026 Research70.1
VRAM by quantization
Memory to load the model and 2K context; below it, the total at 32K and 128K context. Lighter side in bold.
Q2_K
Llama 3.1 405B Instruct
190 GB151.2 GB file
32K 206 GB · 128K 259 GB
GLM 5.3 Flash
138 GB114.2 GB file
32K 161 GB · 128K 234 GB
Q3_K_S
Llama 3.1 405B Instruct
195 GB177.1 GB file
32K 212 GB · 128K 265 GB
GLM 5.3 Flash
not listed
Q3_K_M
Llama 3.1 405B Instruct
218 GB~197.8 GB file
32K 234 GB · 128K 287 GB
GLM 5.3 Flash
158 GB149.1 GB file
32K 181 GB · 128K 254 GB
Q4_K_M
Llama 3.1 405B Instruct
268 GB~243.5 GB file
32K 284 GB · 128K 337 GB
GLM 5.3 Flash
195 GB188.7 GB file
32K 217 GB · 128K 290 GB
Q5_K_M
Llama 3.1 405B Instruct
318 GB~289.2 GB file
32K 335 GB · 128K 387 GB
GLM 5.3 Flash
231 GB244.7 GB file
32K 253 GB · 128K 326 GB
Q6_K
Llama 3.1 405B Instruct
368 GB~334.8 GB file
32K 385 GB · 128K 438 GB
GLM 5.3 Flash
267 GB~265.1 GB file
32K 290 GB · 128K 362 GB
Q8_0
Llama 3.1 405B Instruct
446 GB~405.9 GB file
32K 463 GB · 128K 516 GB
GLM 5.3 Flash
323 GB341.0 GB file
32K 346 GB · 128K 418 GB
8 more quants
IQ2_XXS
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
90.2 GB101.8 GB file
32K 113 GB · 128K 185 GB
IQ2_XS
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
98.2 GB92.1 GB file
32K 121 GB · 128K 193 GB
IQ2_S
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
102 GB113.6 GB file
32K 125 GB · 128K 197 GB
IQ3_XXS
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
126 GB120.4 GB file
32K 149 GB · 128K 221 GB
IQ3_S
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
138 GB149.6 GB file
32K 161 GB · 128K 234 GB
IQ3_M
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
146 GB150.7 GB file
32K 169 GB · 128K 242 GB
IQ4_XS
Llama 3.1 405B Instruct
not listed
GLM 5.3 Flash
175 GB156.8 GB file
32K 197 GB · 128K 270 GB
BF16
Llama 3.1 405B Instruct
893 GB~811.7 GB file
32K 909 GB · 128K 962 GB
GLM 5.3 Flash
644 GB641.6 GB file
32K 667 GB · 128K 740 GB
Llama 3.1 405B Instruct
Ollama · Q4_K_M
ollama run hf.co/MaziyarPanahi/Meta-Llama-3.1-405B-Instruct-GGUFGLM 5.3 Flash
Ollama · Q4_K_M
ollama run hf.co/batiai/GLM-5.3-Flash-GGUF:Q4_K_M| Spec | Llama 3.1 405B Instruct | GLM 5.3 Flash |
|---|---|---|
| Publisher | Meta | Z.ai |
| Parameters | 405.9B | 321.3B |
| Active parameters | — | 18B per token |
| Architecture | — | Glm5NextForConditionalGeneration |
| Context | — | 1M tokens |
| Modalities | Chat, Function-calling | Vision, Function-calling |
| License | Llama 3.1 Community | MIT |
| Released | Jul 2024 | Aug 2026 |
Frequently Asked Questions
Which is better, Llama 3.1 405B Instruct or GLM 5.3 Flash?
GLM 5.3 Flash leads llmrun Score 124.1 to 83.5; neither fits 24 GB. Choose Llama 3.1 405B Instruct for also does chat; choose GLM 5.3 Flash for higher llmrun Score and stronger at reasoning.
Which needs less VRAM, Llama 3.1 405B Instruct or GLM 5.3 Flash?
At Q4_K_M, Llama 3.1 405B Instruct requires 267.9 GB while GLM 5.3 Flash needs 194.6 GB, making GLM 5.3 Flash the easier model to run on your local setup.
Can I run Llama 3.1 405B Instruct or GLM 5.3 Flash on a 16 GB GPU?
Llama 3.1 405B Instruct does not fit (smallest quant needs 197.4 GB); GLM 5.3 Flash does not fit (smallest quant needs 100.7 GB).