Picking the wrong quantization during LLM-to-GGUF conversion can cost you 30% accuracy or double latency. We've seen it happen. With 5+ years of experience in model optimization, we guarantee quality. On real projects, we select the optimal quantization for your hardware — so the model fits in memory and hits your speed targets. For a client with a 7B model and 8 GB RAM, we chose Q4_K_M: 20 tok/s on a Core i7, quality loss under 0.5%. In 3–5 days we convert your model and test it on your equipment. Conversion costs start at $500, with savings up to 70% compared to cloud GPU inference.
Why GGUF became the standard for local inference
GGUF (GPT-Generated Unified Format) replaced the older GGML with built-in metadata support, fast loading, and compatibility with llama.cpp, Ollama, LM Studio, and GPT4All. Unlike raw Hugging Face weights, GGUF stores everything needed for inference — tokenizer, configuration — in a single file. It reduces model footprint by 2x, loads 30% faster, and supports quantization out of the box. This is critical for CPU-based systems with memory bandwidth limitations.
Step-by-step conversion process
Step 1: Download convert_hf_to_gguf.py from the llama.cpp repository.
Step 2: Convert to F16 GGUF:
python convert_hf_to_gguf.py /path/to/model --outtype f16 --outfile model-f16.gguf
Step 3: Quantize using llama-quantize:
./llama-quantize model-f16.gguf model-q4_k_m.gguf Q4_K_M
The model is then ready for any compatible inferencing engine. For more details, see the GGUF specification.
Which quantization scheme should you choose?
| Type |
Size (7B model) |
Perplexity loss |
Speed (CPU) |
Use case |
| Q4_K_M |
~4.1 GB |
~0.5% |
~20 tok/s |
Best balance |
| Q5_K_M |
~5.0 GB |
~0.2% |
~18 tok/s |
When RAM allows |
| Q8_0 |
~7.7 GB |
~0.0% |
~15 tok/s |
Maximum quality |
| Q3_K_M |
~3.3 GB |
~1.5% |
~25 tok/s |
Minimum size |
Q5_K_M yields 10–15% better perplexity than Q4_K_M with only a 20% size increase. In fact, Q4_K_M is 20% faster than Q5_K_M, making it superior for speed-critical tasks. If memory is abundant, Q8_0 gives best accuracy but reduces throughput by 1.3x. For comparison, one hour of cloud GPU inference often costs 2–3× more than a full month of local CPU inference from a GGUF checkpoint. Over 100 models converted, we've seen typical infrastructure cost savings of 70% when moving from cloud GPU to local CPU.
What's included in our conversion service
- Model transformation to GGUF (F16 + chosen quantization)
- Selection of optimal quantization for your task and hardware
- Quality testing (perplexity, sample generation) on your target platform
- A report with results and recommendations for further use
- Integration with an inference engine (llama.cpp, Ollama, LM Studio) on request
How we test the model after conversion
After conversion, we always validate on your hardware: measure p99 latency, token generation speed, and compute perplexity on a validation set. If the model is used for a chatbot, we also evaluate response fidelity on typical prompts. Results come as a report with graphs — you see exactly how characteristics changed. Typical infrastructure cost savings when moving from cloud GPU to local CPU with GGUF reach 70%.
Common conversion mistakes and how to avoid them
-
Wrong order of operations: convert to F16 first, then quantize — not the reverse.
-
Architecture incompatibility: not all architectures work with llama-quantize; check compatibility before conversion.
-
Quality loss from aggressive quantization: Q2_K and Q3_K can severely degrade quality; for important tasks choose Q4_K_M or higher.
Comparison with other approaches
| Format |
Size (7B) |
CPU speed |
GPU required? |
Portability |
| Hugging Face (FP16) |
~14 GB |
~5 tok/s |
Yes |
Requires conversion |
| GGUF (Q4_K_M) |
~4.1 GB |
~20 tok/s |
No |
Single file |
| ONNX (INT8) |
~7 GB |
~12 tok/s |
No |
Requires runtime |
GGUF models run 2–3x slower on CPU than on GPU, but the savings in cloud costs offset that. For tasks up to 7B parameters, local CPU inference with GGUF cuts infrastructure costs by 70% compared to cloud GPU instances. Our certified engineers ensure smooth integration with your existing stack.
Timelines and costs
Estimated conversion time: 1 to 5 days depending on model complexity and testing depth. Cost is calculated individually — typically $500-$2000. Contact us to assess your project — we'll find the optimal solution and deliver on time. With a 100% satisfaction guarantee, you have nothing to lose.
Get a consultation on your model conversion right now.
Edge AI and Optimization: How to Deploy Models Without Cloud?
Imagine: your face recognition model has 4 seconds latency on Jetson Orin, the battery runs out in an hour, and the model crashes with OOM. We are a team of Edge AI engineers with 5+ years in production — we have optimized over 150 models for edge devices. Without profiling and proper choice of quantization or distillation, the project is doomed. The gap between research code and edge deployment is a separate engineering discipline; we help you master it in 2–16 weeks turnkey. Edge AI and model optimization services are not just export, but systematic work with hardware.
Why Simply Exporting a Model Doesn't Work?
A PyTorch model with float32 and batch_size=32 is not ready for edge. Typical problems:
- ResNet-50 in fp32 occupies 98 MB, inference on Cortex-A78 — 380 ms. After INT8 quantization via
torch.ao.quantization — 24 MB, 95 ms. Export to ONNX + TensorRT on Jetson — 28 ms.
- YOLOv8m on Raspberry Pi 5 in fp32 — 2.8 fps. TFLite INT8 — 9.4 fps. With XNNPACK delegate — 14 fps (1.5× faster than pure INT8).
- Transformer encoder on mobile CPU: MobileBERT in fp16 via CoreML on iPhone 15 — 18 ms/inference.
distilbert-base-uncased in ONNX — 42 ms.
The problem is not choosing "quantize or not" — the right path is determined by the device, task, and acceptable metric degradation. We offer an assessment of your project: within 24 hours we will tell you how feasible it is to speed up the model.
How to Choose Quantization Method for Your Task?
PTQ (Post-Training Quantization) — a quick path. Take a trained model, run a calibration dataset (200–1000 samples), get INT8 or INT4 weights. Tools: torch.ao.quantization, ONNX Runtime quantization tool, bitsandbytes. Accuracy degradation: 0.5–2% on classification. Red zone — small object detection and segmentation, where PTQ gives -4–8% mAP.
QAT (Quantization-Aware Training) — training with simulated quantization noise. More expensive (retraining), but degradation 0.1–0.5%. Justified when PTQ is unacceptable. In PyTorch — torch.ao.quantization.prepare_qat().
GPTQ / AWQ — for LLMs. AWQ better preserves quality at 4-bit quantization. llm-compressor from Neural Magic or autoawq are the main libraries.
| Method |
Implementation Time |
Accuracy Degradation |
Tools |
| PTQ |
1–2 days |
0.5–2% (up to 8% on detection) |
torch.ao, ONNX RT, bitsandbytes |
| QAT |
1–3 weeks |
0.1–0.5% |
torch.ao.prepare_qat, TF Quantization |
| GPTQ/AWQ |
3–7 days |
1–3% (LLM) |
autoawq, llm-compressor |
Potential savings from choosing the right method can be substantial — for example, reducing cloud inference costs by up to 70% when deploying to edge. Project cost is calculated individually based on model complexity and target platform.
When to Use Pruning vs Distillation?
Structural pruning removes channels or layers. torch.nn.utils.prune — basic tool. For transformers — attention head pruning (LTP, movement pruning). Result: ResNet-50 after removing 40% of channels with fine-tuning — -35% size, -28% latency, -1.2% top-1 accuracy.
Knowledge distillation — train a small student to mimic a large teacher. Classic via KLDivLoss on soft labels. Feature distillation on intermediate layers is more effective. Hugging Face DistilBERT: 66M vs 110M parameters, -40% latency, -3% on GLUE. This is a model compression technique.
Combined approach: distillation → pruning → QAT. Gives maximum effect on limited hardware. We recorded a case where a client achieved 70% reduction in cloud compute spend after moving to edge with this pipeline.
Target Platforms and Tools
| Platform |
Preferred Format |
Tool |
Specifics |
| NVIDIA Jetson |
TensorRT engine |
trtexec, torch2trt |
INT8 calibration, DLA offload |
| Apple Silicon / iOS |
CoreML (.mlmodel) |
coremltools |
ANE (Neural Engine) automatically |
| Android |
TFLite (.tflite) |
tf.lite.TFLiteConverter |
GPU delegate, NNAPI |
| x86 CPU |
ONNX + ORT |
onnxruntime |
AVX-512, VNNI |
| Arm Cortex |
TFLite / ONNX |
ort-arm, tflite |
XNNPACK, NEON |
| Qualcomm NPU |
QNN (.dlc) |
Qualcomm AI Hub |
Hexagon DSP |
TensorRT — the main tool for NVIDIA edge. TRT builds a graph with operator fusion, selects optimal kernels. On Jetson AGX Orin YOLOv8m in TRT INT8 gives 78 fps vs 22 fps in fp16 PyTorch — 3.5× improvement.
Practical Case: How We Detected Defects on a Production Line (Our Client)
Task: real-time scratch detection on metal, 30 fps, camera to Jetson Xavier NX (16GB). Original model YOLOv8l mAP50 0.91, server inference 28 ms, on Jetson in fp16 — 110 ms (9 fps). Not suitable.
Optimization steps we performed for our client:
- Switch to YOLOv8m — mAP50 0.887 (-2.3%), 68 ms
- Export to TensorRT FP16 via
yolo export format=engine half=True — 31 ms (32 fps)
- INT8 calibration on 500 frames — 22 ms (45 fps), mAP50 0.879
Result: 3.5% degradation at 5× speedup. Client received engine and documentation. We guarantee metric will not drop below agreed threshold — specified in contract.
Example model profiling (layer latency)
Profile slice of YOLOv8m on Jetson Xavier NX (fp16):
- Convolution (layer 1–5): 12 ms
- Bottleneck (layer 6–10): 8 ms
- Head (detection): 11 ms
Bottleneck is the last layers of the head. After quantizing the head separately, head latency dropped to 4 ms.
What is Included in the Work?
- Report on model profiling on target device (layer latency, bottlenecks)
- Selection and justification of optimization methods (quantization / pruning / distillation)
- Optimized model (TensorRT engine / TFLite / CoreML / ONNX)
- Configs for reproducibility (scripts, Docker image, instructions)
- Testing on real device (at least 10,000 inferences)
- Training of your team (2 hours online)
- 1 month support after delivery
How to Order Model Optimization
- Submit a request on the website or contact us in any convenient way.
- We perform free profiling of your model on the target device within 24 hours.
- We prepare an optimization plan with trade-off estimates (speed vs quality).
- You approve the plan — we start work.
- After completion, we deliver the optimized model, configs, and documentation.
- We train your team and provide monthly support.
Timeline: optimization of an existing model — 2–4 weeks. Development from scratch for edge — 6–16 weeks.
Get a consultation — we will evaluate your model for free and offer a plan within 24 hours. Order free profiling now. For complex projects, contact our engineering team to discuss custom optimisation strategies.