Structured Logs for .NET Apps

Get visibility to resolve issues fast

Seq is the easiest way for .NET developers to capture, search and integrate structured log events. Compared with traditional plain-text logs, structured logs cut through the complexity of distributed and asynchronous applications.

By increasing visibility into running apps from development through to production, Seq helps your team identify and resolve issues fast.

Seq has already solved several visibility problems
— Arri Rucker, City Corridor

Install in seconds

Seq is a self-hosted web application you can install on-premises or in the cloud. Authentication, API keys and full support for SSL at the logging endpoint keep your data safe.

Maintaining total control over your log data on your own infrastructure makes Seq a perfect fit for industries with sensitive data management requirements. Businesses in 25 countries rely on Seq every day.

Log structured events

Seq integrates deeply with the Serilog library to preserve the structure of log event data for revolutionary filtering and correlation.

To get started install the Serilog.Sinks.Seq package from Visual Studio's NuGet console:

PM> Install-Package Serilog.Sinks.Seq

Point a logger to Seq:

var log = new LoggerConfiguration() .WriteTo.Seq("http://localhost:5341") .CreateLogger();

And use the Serilog message template DSL to associate named properties with log events:

log.Error("Failed to log on user {ContactId}", contactId);

Not using Serilog? We think you should give it a try, but Seq also has support for other popular .NET logging frameworks including SLAB, log4net and NLog. You can find instructions in the Seq documentation.

When you log structured data, Seq lets you "reach inside" events with a C#-inspired query syntax for ultimate filtering and correlation. Query with all the operators you'd expect: numeric comparisons, text searching, regular expressions and more.

Search by Property
Seq Apps

Use log events to trigger email notifications, raise tickets in a tracking system, or notify your team in Slack and HipChat. Integrations from us and from the community are published on NuGet.

Create new integrations and extensions in C# using the Seq Apps plug-in system. Or, integrate Seq with your existing tools and applications with its powerful HTTP API.

Quickly drill down into occurrences of an event with Seq's histogram view, or track occurrences over time with the built-in dashboard.

Property-aware CSV export makes it easy to perform further analysis in Excel and traditional reporting tools.


Get started now

Seq is provided with a free single-user license - just download the installer and go!

Try Seq's professional features including authenticated access and SSL free for 30 days. When you're ready, choose a paid license to suit your team.