Express Error and Performance Monitoring

Actionable insights to resolve Express performance bottlenecks and errors. Improve your Express monitoring workflow with a full view of releases so you can mark errors as resolved and prioritize live issues.

Getting Started is Simple

Add @sentry/node as a dependency:

Bash
npm install --save @sentry/node

Sentry should be initialized as early in your app as possible:

JavaScript
import express from "express";
import * as Sentry from "@sentry/node";

// or using CommonJS
// const express = require('express');
// const Sentry = require('@sentry/node');

const app = express();

Sentry.init({ dsn: "https://<key>@sentry.io/<project>" });

// The request handler must be the first middleware on the app
app.use(Sentry.Handlers.requestHandler());

// All controllers should live here
app.get("/", function rootHandler(req, res) {
  res.end("Hello world!");
});

// The error handler must be before any other error middleware and after all controllers
app.use(Sentry.Handlers.errorHandler());

// Optional fallthrough error handler
app.use(function onError(err, req, res, next) {
  // The error id is attached to `res.sentry` to be returned
  // and optionally displayed to the user for support.
  res.statusCode = 500;
  res.end(res.sentry + "\n");
});

app.listen(3000);
Powered by OpenTelemetry

Powered by OpenTelemetry

Sentry works with OpenTelemetry to provide a simple configuration process, and rich distributed tracing context across all the libraries and frameworks used in your application. Regardless of your chosen tech stack.

Express Performance Monitoring

Quickly identify Express performance issues and view full end-to-end distributed trace to see the exact, poor-performing API call and surface any related errors.

Express Error Monitoring with Complete Stack Traces

See the Express source code at each frame instead of settings for just line and column numbers. Get proper asynchronous context tracking — like thread-local store — in a way that fits Node's concurrency model.

Fill In The Blanks About Express Errors

See what the app was doing when the Express error occurred: HTTP requests, database queries, console loft statements, etc.

Express Application Profiling

Profiling lets you see what parts of your code are consuming the most resources, like CPU or memory, in your application— so you can optimize them before end user experience is impacted. Test your application performance in any environment, including in production, without writing manual tests or extensive troubleshooting.
Try Profiling

"Sentry's high-quality tooling helps Disney+ maintain high-quality service to its tens of millions of global subscribers."

Andrew Hay
Director of Engineering
Disney Streaming Services

See the Full Picture of Any Exception

Aggregate errors by factors like request details, user ID, and event level to see what's new, a priority, or a trend.

Assign custom key-value tags to reproduce the error environment specific to your application, business, and users.

Find answers to key questions: Has an error with the same stack occurred before? In which app release did the Express bug occur?

It's why companies that don't have a complete view of their infrastructure are being punished:

The average cost of network downtime is around $5,600 per minute — or $300,000 per hour.

1 out of 5 online shoppers will abandon their cart because the transaction process was too slow.

On average, a two-second slowdown in page load decreases revenues by 4.3 percent.

FAQs

Traditional logging provides you with a trail of events. Some of those events are errors, but many times they're simply informational. Sentry is fundamentally different because we focus on exceptions, or in other words, we capture application crashes. We discuss in more detail here and on our blog.

Sentry supports every major language, framework, and library. You can browse each of them here.

You can get started for free. Pricing depends on the number of monthly events, transactions, and attachments that you send Sentry. For more details, visit our pricing page.

Sentry doesn't impact a web site's performance.

If you look at the configuration options for when you initialize Sentry in your code, you'll see there's nothing regarding minimizing its impact on your app's performance. This is because our team of SDK engineers already developed Sentry with this in mind.

Sentry is a listener/handler for errors that asynchronously sends out the error/event to Sentry.io. This is non-blocking. The error/event only goes out if this is an error.

Global handlers have almost no impact as well, as they are native APIs provided by the browsers.

Yes. The Sentry Node.js SDK supports both CommonJS and ECMAScript modules, and instruments worker threads as well as your main process. On Node 18.19.0+ and 19.9.0+ it can also use TracingChannel diagnostics for more accurate instrumentation.

Sentry ships integrations for Express, Fastify, NestJS, Koa, Hapi, Connect and dozens of other JavaScript frameworks, plus OpenTelemetry support if you already have an OTel pipeline.

Yes. The Node.js SDK includes MCP (Model Context Protocol) server monitoring and agent tracing, so tool calls and agent steps show up as spans on the same traces as the rest of your backend.

That means a failing tool call, a slow model response, and the HTTP request that triggered them all sit on one trace. Learn more about AI Agent Monitoring.

Yes. Sentry Logs lets you send, view, and query structured logs from your application alongside your errors and traces. Because logs sit next to the error and the trace that produced them, you get the granular context — retries, API failures, internal state — that spans and stack traces alone can miss, without switching tools.

Learn more about Logs in Sentry.

Seer is Sentry's AI debugging agent. It reads the full context Sentry already has — the error, its stack trace, the surrounding trace, logs, and profiles — to find the root cause of an issue and propose a fix. Seer can open a pull request with that fix, hand the work to an external coding agent, or review your PRs before they ship.

Learn more about Seer and Autofix.

A better experience for your users. An easier life for your developers.