Learn ONNX with Real Code Examples
Updated Nov 24, 2025
Practical Examples
Convert a PyTorch CNN to ONNX and run inference on CPU
Optimize a BERT model using ONNX Runtime for GPU
Deploy a scikit-learn RandomForest model using ONNX
Run quantized ONNX model on mobile device for reduced memory
Integrate ONNX model into cloud-based inference service
Troubleshooting
Verify all operators are supported in ONNX version
Check input/output tensor shapes match original model
Debug custom layers using ONNX Runtime custom ops
Ensure correct version of ONNX and runtime
Validate inference results against original framework outputs
Testing Guide
Compare outputs of ONNX model to original framework
Test with different batch sizes
Validate on multiple hardware backends
Check performance before and after optimization
Ensure numerical precision matches original model
Deployment Options
Run ONNX model via ONNX Runtime on server CPU/GPU
Deploy quantized models on mobile or embedded devices
Integrate with cloud ML inference pipelines
Use containerized ONNX Runtime environments
Combine multiple ONNX models in a pipeline for ensemble inference
Tools Ecosystem
ONNX converters for PyTorch, TensorFlow, scikit-learn, Keras
ONNX Runtime for CPU/GPU inference
ONNX Model Zoo with pre-trained models
Quantization and optimization tools (`onnxruntime-tools`)
Integration with cloud ML services and mobile SDKs
Integrations
PyTorch, TensorFlow, Keras for model export
ONNX Runtime for cross-platform inference
TensorRT and OpenVINO for hardware acceleration
Edge devices like NVIDIA Jetson, Intel Movidius
Cloud deployment on AWS, Azure, GCP
Productivity Tips
Use ONNX Runtime for optimized inference
Apply quantization to reduce model size
Validate models after each conversion
Use graph optimization tools for speed
Batch inputs to maximize throughput
Challenges
Handling unsupported or custom operators
Debugging conversion discrepancies
Optimizing for hardware-specific inference
Ensuring numerical precision matches original model
Maintaining model versioning across multiple deployments