Structured Logs for .NET Apps

Ship better .NET software, faster

Seq is the easiest way for .NET developers to capture, search and integrate structured log events.

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

Build, Test, Deploy, Monitor

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.

Log structured events

Seq can accept events from log4net, NLog and SLAB, but capturing structured events from Serilog is where Seq really shines!

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

PM> Install-Package Seq.Client.Serilog

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.Information("Customer {CustomerId} logged on", customerId);

Serilog supports logging to multiple sinks, so you can use the console or a flat log file too if you like.

Query using a natural syntax

Seq has full text-searching capabilities including regular expressions. You don't give up any flexibility by using structured logs.

When you log structured data, Seq lets you "reach inside" events with a C#-inspired query syntax for ultimate filtering and correlation. If an event includes numeric data, query with all the comparisons you'd expect: <, <=, == and so-on.

Search by Property


Take advantage of community-published apps to process events, or write your own.

Apps can be triggered to send email or instant messages, post to issue trackers, or relay data to existing BI infrastructure.

Featured Apps

Find the perfect fit

Seq is provided with a free single user license - just download the installer and go! Register your copy to enable all features including authentication.

Try Seq's professional features free for 30 days to see it in action. When you're ready, choose a paid license to suit your team.