Microsoft is shutting down the Azure AI Anomaly Detector service on October 1, 2026. New resources have been blocked since September 2023; existing resources stop working on the retirement date. If your alerting, monitoring, or IoT pipeline calls the
/anomalydetector/v1.1 API, you need a migration plan — ideally with enough buffer to test before the deadline.
This guide compares every realistic option, including the ones that don't involve us.
| Option | Effort | Best when… | Watch out for |
|---|---|---|---|
| Microsoft Fabric (time-series-anomaly-detector package) | High | You already use Fabric/Eventhouse and want to stay all-Microsoft | Not an HTTP API — you rewrite your integration as Spark/Python code; Fabric capacity pricing |
| Open-source engine (microsoft/anomaly-detector on PyPI) | Medium–High | You have Python infrastructure and want zero license cost | You own hosting, scaling, monitoring, and updates; heavy dependency chain (incl. PyTorch for multivariate) |
| Azure Stream Analytics / Data Explorer | Medium | Your data already flows through these services | Different programming model (SQL functions, not a REST call); results differ from the old API |
| Drop-in API replacement (Anomatik, Canary Edge) | Minimal | You want your existing integration to keep working unchanged | Third-party dependency; check data residency and pricing |
| Build your own (Prophet, PyOD, statsmodels…) | High | Anomaly detection is core to your product and you have DS capacity | Months of effort for something that was one API call |
Microsoft's recommended migration is to Microsoft Fabric, which integrates the same algorithms via the time-series-anomaly-detector package, running as Spark or inline Python against Eventhouse. If your organization is already invested in Fabric, this keeps everything under one roof and adds multivariate detection.
The catch: it is not an API. The old integration — POST a JSON series, get flags back — has no direct equivalent. You'll re-implement your detection step inside notebooks or pipelines, and you pay for Fabric capacity, which is a very different cost model from per-transaction pricing. For a team that only ever used the REST endpoint, this is the heaviest migration on the list.
Microsoft open-sourced the detection engine (PyPI: time-series-anomaly-detector). It's genuinely the same math that powered the service, and it's free. If you have a Python service anyway, you can import it and detect locally.
Budget for the operational reality: the package pulls a large dependency chain (PyTorch and MLflow for the multivariate part), you'll wrap it in your own service for HTTP access, and you own uptime, scaling, and security patching from then on. "Free" here means "free like a puppy".
Both offer built-in anomaly functions (AnomalyDetection_SpikeAndDip, series_decompose_anomalies()). If your telemetry already lives there, using the native functions is pragmatic. But it's a different paradigm — SQL-style functions over streams instead of a stateless REST call — and the detection results won't match the old API exactly, so re-tune your thresholds and alerts.
If your goal is "keep everything working, change as little as possible", a compatible third-party API is the shortest path. Your code, SDK calls, parsing, and dashboards stay untouched — you swap the endpoint URL and the API key:
# before https://<resource>.cognitiveservices.azure.com/anomalydetector/v1.1/timeseries/entire/detect # after https://api.anomatik.de/anomalydetector/v1.1/timeseries/entire/detect
Two services currently offer this:
Prophet, PyOD, statsmodels, or a hand-rolled seasonal-decomposition + robust-scoring pipeline can absolutely replicate what the API did — we know, because that's essentially what we built. Realistically it's weeks to months of work to get edge cases right (seasonality detection, margins, sensitivity semantics), plus permanent ownership. Worth it only if anomaly detection is a core differentiator of your product.
Whatever you choose: don't wait until September. The teams that migrate calmly in July and August get to A/B-test against the live Azure API while it still exists — that option disappears forever on October 1, 2026.