Guide 05 · Debugging · GA4 + Tag Manager
DebugView: find your own event in the stream and read its parameters
DebugView shows only devices in debug mode, one event at a time with its parameters. Pick your device, pick the minute, and the event is either there or it is not.
After the steps below, your device is selected in DebugView, your event appears in the Seconds stream within a minute, and its parameters read exactly as the tag sent them.
Download the check: the debugging check (JSON) (MD5 7d646817cb3b1b6466074ef168f10127, 496 bytes). It lists the checkpoints from this guide and the worked check, with the figures recomputed. The file was built for this guide and validated structurally — it was not exported from a live container or a live property.
What you need
- Debug mode on for your device. Tag Assistant or Preview mode adds the debug signal to your session; without it, DebugView has nothing to show for you.
- Access to the GA4 property. DebugView lives under Admin, then Data display, so you need a role that can open Admin on the property.
- The event name, spelled exactly. Event names are case-sensitive, so write down the name the tag sends before you go looking for it.
- One test action, done once. Do the action a single time, then look. Doing it five times first makes the stream hard to read.
The trace
The worked check: the figures below were recomputed before publication, and the note under the table shows the working.
| Check | Figure |
|---|---|
| Events logged in the last 30 minutes | 42 |
| Events from the test device | 9 |
| Events with the expected name | 9 |
| Seconds-stream window | 60 seconds |
| Minutes-stream window | 30 minutes |
The Minutes stream held 42 events across 30 minutes, and 9 of them came from the test device — 42 minus 9 is 33 events from other devices, which is why the device selector matters. All 9 test-device events carried the expected name, so 9 of 9 matched. The Seconds stream covers the last 60 seconds and the Minutes stream the last 30 minutes.
- Turn debug mode on for your own device. Use Tag Assistant at tagassistant.google.com, or Preview mode in Tag Manager. Tag Assistant adds a parameter to your website address to enable debug mode for your session. This marks your device only, so other visitors never appear in your stream.
- Open DebugView. In Analytics, go to Admin, then under Data display, click DebugView. The report has three columns: the Minutes stream on the left, the Seconds stream in the middle, and Top Events and user properties on the right.
- Pick your device. If more than one device has debug mode on, use the DEBUG DEVICE selector at the upper left to choose your own. Without this step you may be reading another developer's events and concluding your tag is broken when it is not.
- Do the test action once, then watch the Seconds stream. The Seconds stream shows the events logged in the last 60 seconds, newest at the top. Do your action once and look for the event name within a minute. Click the event to see its parameters.
- Read the parameters, not just the name. Clicking the event lists every parameter it carried. Check the ones the report needs — for an ecommerce event, the transaction ID, the value, the currency, and the items array. An event with the right name and the wrong value is still a broken event.
Dead ends
DEAD END — THE STREAM IS EMPTY BECAUSE DEBUG MODE IS OFF. DebugView only shows devices with debug mode on. An empty DebugView with debug mode off proves nothing about your tag. Turn debug mode on first, then read the stream.
DEAD END — READING EVERYONE'S EVENTS AT ONCE. With several devices in debug mode and no device selected, the stream mixes them together. Your event may be there under another device's name, or absent while others flood the list. Select your device before you conclude anything.
DEAD END — LOOKING AT THE WRONG MINUTE. The Seconds stream covers 60 seconds. If you did the action three minutes ago and you are staring at the Seconds stream, the event has already scrolled into the Minutes stream. Click the minute circle for the minute you acted.
End state
Your device selected, your event found in the Seconds stream within a minute of the action, and its parameters read and matched against what the tag should send. If the event is here, the tag and the property are right and the problem is downstream, in the report. If it is not here, the break is upstream, in the tag or in consent.
Sources
- Analytics Help — Monitor events in DebugView — Enabling debug mode for your own device, the DebugView path, the Seconds stream covering 60 seconds, the Minutes stream covering 30 minutes, and the device selector
- Analytics Help — Confirm that you are collecting data — Realtime and DebugView as the two reports that confirm collection sooner than standard reports
Checked 11 November 2026. The click paths above are the ones in Google's help pages, opened 11 November 2026. What was run: the device counts, recomputed — 42 events in 30 minutes, 9 from the test device and 33 from other devices, with 9 of 9 test-device events carrying the expected name. No step in this guide was run inside a live Analytics property or a live Tag Manager container, because both need a Google sign-in and this site does not sign in as anyone. Google moves menu items without warning; if a path on this page no longer matches, the linked help page is the current map.