How Runtime Replay compares to Loom

Replay can be compared to Loom, a video + screen recorder. While both involve recording, the two tools serve different use cases and provide different functionality.

In this post, we’ll quickly explain how they’re different and when you’d use Replay vs. Loom.

TLDR; Replay records the state of your application with built-in developer tools to allow you to actively debug and make changes retroactively. Loom is a screen + camera recorder for any knowledge worker to record videos.

What is Loom?

Loom is a video messaging platform with a screen recorder feature. Engineering teams might use Loom with the console log open to record sessions. You can record your screen, camera or both and share it as a URL with anyone and edit the video as you like. With Loom, you can only comment on parts of the video file, not the code itself.

What is Replay?

Replay records the entire browser session

Replay is for recording everything happening in a particular session of the application. With Replay, we are recording everything, including the user events, network requests, the state of the application at every point in time, and what code was executing during the recording. This makes it particularly useful for reproducing issues and debugging.

Replay is a debugger

Replay is a time-travel debugger that comes along with developer tools you’re familiar with from browsers and IDEs. While other debuggers require you to run your application again and again to debug, Replay provides all these tools in the context of the recording, so print statements can be added retroactively and you can inspect your application at any point in time from the session.

Replay records runtimes and automated tests

Chrome Recorder, as the name implies, is specific to the Chrome browser and records manual user flows. Replay has versions for Firefox and Chromium, and can be used to record automated tests in CI. There is also replay-node-cli for recording Node runtimes, no browser required.

Here is a post on Replay (Time Travel debugging) vs. Session Replay, another common comparison.


Ultimately, if you are more interested in sending a video message and basic functionality of screen recording, you can use Loom or other screen recorders. If you are more interested in the application functionality for validation or debugging, reach for Replay.