RuntimeError
onnxruntime.capi.onnxruntime_pybind11_state.RuntimeError
Stack trace
RuntimeError: [ONNXRuntimeError] : 1 : FAIL : Load model failed:This model uses opset version X which is not supported by this version of ONNX Runtime. Please update ONNX Runtime or export the model with a supported opset version.
Why it happens
ONNX models specify an opset version that defines the set of supported operators and their behavior. If the ONNX runtime or tooling version is older and does not support the model's opset version, it cannot load or run the model, causing this error.
Detection
Check the ONNX model's opset version using onnx.helper or onnxruntime.InferenceSession load errors to detect unsupported opset versions before runtime failures.
Causes & fixes
The ONNX model was exported with a newer opset version than the installed ONNX runtime supports.
Upgrade the ONNX runtime package to the latest version that supports the model's opset version.
The model was exported with an opset version higher than the target deployment environment supports.
Re-export the ONNX model specifying a lower opset version compatible with the deployment environment using the export framework's opset_version parameter.
Mismatch between ONNX package version used to inspect or manipulate the model and the runtime version.
Ensure the ONNX package and ONNX runtime versions are compatible and both support the model's opset version.
Code: broken vs fixed
import onnxruntime as ort
# This will raise RuntimeError if opset version unsupported
session = ort.InferenceSession('model.onnx') # RuntimeError hereimport os
import onnxruntime as ort
# Ensure environment variable for ONNX runtime path if needed
os.environ['ORT_LOG_LEVEL'] = 'verbose'
# Upgrade ONNX runtime to latest version before running
session = ort.InferenceSession('model.onnx') # Fixed by upgrading runtime
print('Model loaded successfully')Workaround
Catch the RuntimeError and programmatically check the model's opset version using onnx.load_model and onnx.helper to decide whether to downgrade the model or notify for runtime upgrade.
Prevention
Always align the ONNX model export opset version with the minimum supported opset version of your deployment ONNX runtime, and keep runtimes updated to support newer opsets.