Exceptionless is an Apache-2.0 licensed, C#-based real-time error reporting service that collects exceptions and crash reports from JavaScript, Node, .NET Core, ASP.NET, Web API, WebForms, WPF, Console, and MVC applications, and it is built for developers and operations teams who need to collect, group, and act on application errors on infrastructure they control.

What it is

Exceptionless is an open-source error monitoring and crash reporting server written primarily in C#, and it lives squarely in the .NET and ASP.NET ecosystem alongside Elasticsearch, which it uses as its backing store. Client applications report exceptions to the service, which organizes the gathered information into simple actionable data and presents it through a web interface and an HTTP API. The repository carries 2,455 stars, 507 forks, and 66 open issues, and its topic list names error-monitoring, error-reporting, crash-reporting, crash-reports, error-stack-trace, bug-tracking-tool, and exception as the areas it covers.

The concrete problem it solves is the raw, ungrouped exception stream that applications otherwise scatter across log files and ad-hoc handlers. Exceptionless centralizes that stream into one searchable place, captures the full stack trace alongside each report, and turns it into data a team can filter and act on. Because the server can be self-hosted under the Apache-2.0 licence, it also replaces the arrangement in which every crash report must be shipped to a vendor-operated endpoint outside the operator's own infrastructure.

Key capabilities

• Real-time error reporting for JavaScript, Node, .NET Core, ASP.NET, Web API, WebForms, WPF, Console, and MVC applications.
• Exception and crash report ingestion with full stack traces grouped into actionable data.
• Elasticsearch-backed storage and search over reported errors.
• Self-contained Docker image published as exceptionless/exceptionless:latest, which runs on port 8080 and is reachable at http://localhost:7110.
• Automatic first-account administrator: the first account created in a fresh instance becomes an admin.
• HTTP API documented in practice through the exceptionless.http request file, usable from Visual Studio Code with the REST Client extension.
• Two front ends in the same repository: the legacy Angular UI in src/Exceptionless.Web/ClientApp.angular, which is still the main site UI, and a Svelte 5 UI in src/Exceptionless.Web/ClientApp that remains under development.

Who uses it and how

• Teams that need error reporting but cannot send crash data to an external vendor run the server themselves, following the self-hosting documentation rather than the hosted service.
• Evaluators and individual developers start the self-contained Docker image to inspect the UI and API without standing up supporting infrastructure, since that instance does not persist data and is only suitable for testing.
• Contributors and maintainers work against Exceptionless.AppHost or the Aspire launch configuration, which starts the application and its required infrastructure together; backend tests bootstrap that infrastructure automatically.
• Organizations that want support attached to self-hosting can use the hosted service or the commercial setup and support offerings, and the project accepts donations and GitHub sponsorships.
• The repository also serves as a reference implementation for .NET developers studying Aspire orchestration, since the application, its infrastructure, and both UI generations are contained in one solution.

Getting started

The quickest route is Docker: run docker run --rm -it -p 7110:8080 exceptionless/exceptionless:latest and open http://localhost:7110. For persistent or production setups, the project directs users to its self-hosting documentation, and for source work the README requires Docker, .NET 10.0, and Node 24 or later before running aspire run from the repository root or starting Exceptionless.AppHost.

How it compares

No competing error monitoring product is named anywhere in the facts provided for this page, so Exceptionless stands alone in this registry and no defensible feature-by-feature contrast can be drawn from the available material. The only relevant distinction the facts do support is internal: the project's own hosted service is offered at a price, while the Apache-2.0 source and the container image can be run on the operator's own hardware.

When to use it — and when not to

Choose Exceptionless when the goal is a self-hosted error reporting service for .NET and JavaScript clients and the operator is prepared to run Elasticsearch and the rest of the required infrastructure, including the supporting components that Exceptionless.AppHost starts. A self-hoster must plan for that operational load and, for anything beyond the throwaway test container, consult the self-hosting documentation, because the single Docker command persists no data and the README is deliberately thin on configuration and defers the details to the external documentation site. Teams that want a fully managed service with no infrastructure to operate, or that require a finished modern front end, should note that the hosted service exists as an alternative and that the Svelte 5 UI is still under active development.