Built for huge logs
A virtualized grid stays smooth at 1M+ lines. Open giant client logs without freezing the browser.
CMTrace. In your browser.
CMTrace.dev is a free, browser-based log viewer for ConfigMgr (SCCM) and Microsoft Intune: a zero-install alternative to the classic CMTrace.exe tool.
It reads the CMTrace log format, legacy SCCM logs and plain text, plus compressed.gz and .ziparchives, and opens them entirely on your device. No file is ever uploaded to a server. A virtualized grid keeps scrolling smooth even past one million lines, severity color-coding highlights errors and warnings at a glance, and built-in Win32/HRESULT/SCCM error-code lookup links straight to Microsoft Learn. It includes ConfigMgr and Intune (IME) presets, a git-style side-by-side log comparison, and an installable offline-capable PWA. Because it runs in any modern browser, it also works on macOS and Linux, where CMTrace.exe was never available. It's a free, independent project built by two Microsoft MVPs, not affiliated with or endorsed by Microsoft.
Drop your log file here
or
.log.lo_.txt.gz.zipopens instantly, 100% in your browser
Runs entirely in your browser. Nothing is uploaded.
1M+Lines, still smooth
100%Client-side
0Installs & accounts
$0Free, forever
Features
Everything CMTrace does, and the bits it never did
A modern reimplementation of the classic CMTrace workflow, built for the logs you actually deal with.
CMTrace, SCCM & plain parsing
Reads the CMTrace format, legacy SCCM/ConfigMgr logs and plain text. It just figures it out.
Severity coloring
Errors, warnings and info are instantly color-coded so failures jump off the screen.
Find, filter & highlight
Search across the whole log, filter by severity or text, and highlight matches as you scroll.
Error-code lookup
Decode Win32, HRESULT and SCCM error codes in place, with one-click links to Microsoft Learn.
Git-style compare
Diff two logs side by side, a good run against a failing one, to spot exactly what changed.
Minimap & insights
A severity minimap and smart timeline surface error clusters and the moments that matter.
ConfigMgr & Intune presets
Jump straight to the right logs with built-in ConfigMgr and Intune Management Extension (IME) presets. Open .gz and .zip too.
Live tail & offline PWA
Follow logs in real time, then install CMTrace.dev as a PWA that works fully offline, with dark mode.
Compare
Diff a good run against a failing one
Drop in two logs and CMTrace.dev lines them up like a git diff, so the one change that broke a deployment is impossible to miss.
- Side-by-side, line-aligned comparison
- Added, removed and changed lines highlighted
- Jump straight to the first divergence
client-A-good.log ↔ client-B-failing.log
Downloading content for app 'ScopeId_2F0…'
+Download complete. Hash verified OK.
-Download failed. CContentDownload 0x80070002
Evaluating detection method for deployment…
Detection inconclusive, retrying (2/3)
+App install succeeded. Exit code 0.
-Install failed. Exit code 1603 (0x80070643)
Updating deployment state to compliant…
Who it's for
Made for people who live in logs
If your day involves execmgr.log, AppEnforce.log or the IME log, this is for you.
ConfigMgr admins
Triage failed app deployments, task sequences and client health straight from the client log files.
Intune admins
Read the Intune Management Extension (IME) logs and Win32 app diagnostics without leaving the browser.
MVPs & consultants
Share a link, not an install. Demo, document and troubleshoot on any machine, on any OS, in seconds.
Who's behind it
Built by two Microsoft MVPs
CMTrace.dev comes out of real day-to-day ConfigMgr and Intune work, not a weekend side project.
Florian Salzmann
Microsoft MVPSwitzerland-based, 14+ years working in Microsoft cloud and endpoint management: Intune, Microsoft Entra ID, endpoint security, Windows 365 and Microsoft Defender.
Full bio →
Jannik Reinhard
Microsoft MVPDual Microsoft MVP for Security (Intune) and AI Platform. Focuses on Intune endpoint operations, Azure cloud architecture and AI agents/automation, including 90+ Intune remediation packages built for real-world environments.
Full bio →Alternative
Is there a browser-based alternative to CMTrace.exe?
Yes: CMTrace.dev reads the same log formats without the download, the install, or the Windows-only limitation.
| CMTrace.exe | CMTrace.dev | |
|---|---|---|
| Install required | Yes, download & extract from ConfigMgr media | No, opens in your browser |
| Works on | Windows only | Windows, macOS, Linux: any modern browser |
| Cost | Free | Free |
| Uploads your logs | N/A, local desktop app | Never, 100% client-side |
| Offline use | Yes | Yes, installable PWA |
| Format support | CMTrace format only | CMTrace, legacy SCCM, plain text, .gz/.zip |
FAQ
Frequently asked questions
Is CMTrace.dev free?
Yes. CMTrace.dev is completely free. There are no accounts, no paywalls and no usage limits. Just open it and start reading logs. It's an independent side project built by two Microsoft MVPs for the ConfigMgr and Intune community, with no premium tier and no plan to add one.
Are my logs uploaded anywhere?
No. CMTrace.dev runs 100% in your browser. Your log files are parsed and rendered locally on your device and are never sent to a server, so it's safe for sensitive ConfigMgr and Intune logs. You can verify this yourself by checking your browser's network tab: nothing is transmitted.
Which log formats does it support?
It reads the CMTrace log format, legacy SCCM/ConfigMgr logs and plain-text logs. You can also open compressed .gz and .zip archives, and use built-in ConfigMgr and Intune (IME) presets. Format detection is automatic, so you don't need to know in advance which type of log you're opening.
How large a log file can it handle?
The grid is virtualized and stays smooth at one million-plus lines. Only the visible rows are rendered, so large client logs scroll without freezing the browser. That matters in practice because busy ConfigMgr clients can produce logs with hundreds of thousands of lines: the kind of file that stalls a plain text editor opens instantly here.
Can I install it or use it offline?
Yes. CMTrace.dev is an installable Progressive Web App (PWA). Install it from your browser and it works offline, just like a desktop app, with no network connection required to read logs. Once installed it opens directly from your taskbar or dock like any other app, and keeps working while traveling or on a locked-down network with no internet access.
Is CMTrace.dev affiliated with Microsoft?
No. CMTrace.dev is an independent open project and is not affiliated with or endorsed by Microsoft. CMTrace is a Microsoft tool and trademark; this is a browser-based reimplementation of that workflow. It doesn't include or redistribute any Microsoft binaries or proprietary code. It was built from scratch for the ConfigMgr and Intune admin community.
Do I need to download CMTrace.exe, or is there an alternative?
You don't need to download or install anything. CMTrace.dev is a free, zero-install alternative to the classic CMTrace.exe tool: open it in your browser instead of hunting for the Microsoft download or extracting it from ConfigMgr install media. It reads the same CMTrace and legacy SCCM log formats, and it also works on macOS and Linux, where CMTrace.exe was never available at all.
Ready when you are
Open your next log in the browser
No install, no upload, no waiting. Drop in a log and start tracing.