DefiledAI Tools

CONTEXT LENGTH CALCULATOR

Calculate the maximum context length your GPU can support for any model and quantization. KV cache is often the hidden VRAM cost.

Model

Weight Quant

KV Cache Quant

Context Length: 4,096 tokens

Your GPU VRAM (GB)

VRAM Breakdown

Model weights (Q4_K_M)0.04 GB

KV cache (4,096 ctx, F16)2.15 GB

Runtime overhead0.50 GB

Total2.69 GB

✓ Fits — 21.3GB headroom

Max Context on Your GPU

43K

tokens at Q4_K_M weights + F16 KV cache

Model supports up to 128K — VRAM is the limiting factor

Switch KV cache to Q4 to get: ~131,072 tokens

Why does context matter?

KV cache grows linearly with context length. At 4K tokens it is small; at 32K+ it can exceed model weight size. Use Q8 or Q4 KV cache quantization (supported in llama.cpp and ExLlamaV2) to extend context without adding VRAM.