Quick Answer
librewolf.exe is safe. It's LibreWolf, a privacy-focused browser based on Firefox, using multiple processes for tabs, extensions, and internal functions to improve security and stability.
What is librewolf.exe?
librewolf.exe is the executable for the LibreWolf web browser, a privacy-focused fork of Firefox. LibreWolf uses a multi-process architecture so each tab, extension, and component can run in its own process. This isolation improves security, stability, and privacy by sandboxing tabs and limiting cross-site access.
LibreWolf distributes tasks across multiple processes (Browser, Renderer, Extension, etc.). This reduces a single crash impact and enhances privacy by restricting telemetry and limiting inter-process interactions within the browser.
Quick Fact: LibreWolf inherits Firefox’s architecture and adds privacy-focused defaults, minimizing telemetry and blocking many trackers by default.
Types of LibreWolf Processes
- Browser Process: Main LibreWolf window and user interface (1 instance)
- Renderer Process: Each tab and iframe (multiple instances)
- GPU Process: Hardware acceleration and graphics rendering
- Extension Process: Each LibreWolf extension gets its own process
- Plugin Process: For plugins like PDF viewer
- Utility Process: Background tasks and network services
Is librewolf.exe Safe?
Yes, librewolf.exe is safe when it's the legitimate file from the LibreWolf project downloaded from official sources (librewolf.net or GitHub releases).
Is librewolf.exe a Virus or Malware?
The real librewolf.exe is NOT a virus. However, malware can impersonate it. Verify the file location and signature as described.
How to Tell if librewolf.exe is Legitimate or Malware
- File Location: Must be in C:\Program Files\LibreWolf\librewolf.exe or C:\Program Files (x86)\LibreWolf\librewolf.exe. Any librewolf.exe elsewhere is suspicious.
- Digital Signature: Right-click librewolf.exe -> Open file location -> Right-click librewolf.exe -> Properties -> Digital Signatures. Should show 'LibreWolf Project'.
- Resource Usage: Normal usage is 3-25% CPU per tab, 150-700 MB total memory. Extremely high usage when LibreWolf is closed is suspicious.
- Behavior: LibreWolf should only run when you open the browser. Multiple instances when LibreWolf is closed indicates malware.
Red Flags: If librewolf.exe is located in unusual folders (like Temp, AppData\Roaming, or System32), runs when LibreWolf isn't open, has no digital signature, or uses excessive resources constantly, scan your system with antivirus software. Beware of similarly-named files like "librewolfx.exe".
Why Is librewolf.exe Running on My PC?
librewolf.exe runs when you open LibreWolf or when LibreWolf is configured to run in the background.
Reasons it's running:
- Active Browser Use: You're actively browsing with LibreWolf - each tab creates a separate process
- Background Extensions and Sync: Extensions or Firefox Sync that operate in the background can keep processes alive
- Startup Launch: LibreWolf is configured to launch automatically when Windows starts
- Background Updates: LibreWolf checks for updates in the background and may start related processes
- Session Restore: Restoring a large previous session with many tabs can spawn multiple processes
Can I Disable or Remove librewolf.exe?
Yes, you can disable librewolf.exe. It's safe to close LibreWolf when not in use, and you can uninstall it completely if you prefer a different browser.
How to Stop librewolf.exe
- End Individual Tabs: Close specific tabs manually, or use about:performance to identify heavy tabs and close them
- Close Browser: Click the X button or use Ctrl+Shift+W to close all LibreWolf windows
- End All Processes: Open Windows Task Manager (Ctrl+Shift+Esc), find librewolf.exe, right-click → End Task
- Prevent Startup: Task Manager → Startup tab → Disable LibreWolf
- Stop Background Tasks: LibreWolf Settings → Privacy & Security → Background Tasks (disable background activity if available)
How to Uninstall LibreWolf
- ✔ Windows Settings → Apps → Apps & Features → LibreWolf → Uninstall
- ✔ Control Panel → Programs → Uninstall a program → LibreWolf → Uninstall
- ✔ Consider alternative browsers: Firefox, Chromium-based, or other privacy-focused options
Common Problems: High CPU or Memory Usage
If librewolf.exe is consuming excessive resources:
Common Causes & Solutions
- Too Many Tabs Open: Each tab uses memory; close unused tabs or use tab management extensions
- Resource-Heavy Extensions: Extensions run continuously in background. Go to about:addons and disable unnecessary ones
- JavaScript-Heavy Websites: Modern web apps (mail, social, video) consume significant resources. Close or reload problematic tabs
- Malicious Extensions: Some extensions contain malware. Remove suspicious extensions immediately
- Outdated LibreWolf Version: Update LibreWolf to latest version: about:preferences#updates or from the official site
- Hardware Acceleration Issues: Try disabling: LibreWolf Settings → General → Performance → Use hardware acceleration when available
Quick Fixes:
1. Identify heavy tabs/extensions via about:performance and close them
2. Clear browsing data: Ctrl+Shift+Delete (select Cached Web Content)
3. Disable unnecessary extensions in about:addons
4. Update LibreWolf: about:preferences#updates
5. Restart LibreWolf and test with a minimal session
Frequently Asked Questions
Is librewolf.exe a virus?
No, the legitimate librewolf.exe from the LibreWolf project is not a virus. Verify the file location and signature: C:\Program Files\LibreWolf\librewolf.exe and a signature from 'LibreWolf Project'.
Why is librewolf.exe using so much CPU?
High CPU can come from JavaScript-heavy pages, many tabs, or a misbehaving extension. Use about:performance to identify culprits, close or disable them, and update LibreWolf.
Can I delete librewolf.exe?
Yes, you can uninstall LibreWolf through Windows Settings → Apps or Control Panel. Your data may be preserved if not synced; back up if needed before uninstalling.
Can I disable librewolf.exe?
Yes, you can close LibreWolf or disable startup via Task Manager's Startup tab. To prevent background activity, adjust LibreWolf settings or disable background tasks.
Why is librewolf.exe running at startup?
LibreWolf may be configured to start with Windows. Disable startup in Task Manager → Startup or modify your startup programs to stop automatic launch.
Why are there so many librewolf.exe processes?
LibreWolf uses a multi-process architecture for security and stability; each tab, extension, and plugin can run in its own process. This can look like many processes in Task Manager.