Quick Answer
clion64.exe is safe. It is the JetBrains CLion IDE executable. It runs UI, indexing, and background analysis processes when a C/C++ project is open.
Is it a Virus?
✔ NO - Safe
Must be in C:\Program Files\JetBrains\CLion <version>\bin and signed by JetBrains s.r.o.
Warning
Many CLion processes
Indexing, builds, and background analyzers spawn multiple clion64.exe/+ helper processes
Can I Disable?
✔ YES
Close CLion or disable indexing/build in Settings to reduce background activity
What is clion64.exe?
clion64.exe is the executable for JetBrains CLion, the cross‑platform C/C++ IDE. CLion runs as a set of processes: the main UI, indexers, and background tasks, especially when a CMake project is loaded, enabling code analysis and navigation.
CLion uses a multi‑process model with UI, indexing, and background services. It leverages CMake for project configuration and LLDB/GDB for debugging, offering inline insights, refactorings, and static checks via clang-tidy.
Quick Fact: CLion's indexing and code analysis run in separate background processes to keep the editor responsive while parsing large C/C++ codebases.
Types of CLion Processes
- UI Process: Main CLion window and user interface (single or few instances)
- Indexer Process: Code indexing and semantic analysis for fast navigation
- Build/Configuration Process: CMake configuration and project generation tasks
- Debugger Helper: LLDB/GDB integration for debugging sessions
- Plugin/Utility Process: Plugins or auxiliary CLion services (linting, formatting)
- VCS/Background Service: Version control integrations and background checks
Is clion64.exe Safe?
Yes, clion64.exe is safe when it is the legitimate JetBrains CLion executable downloaded from JetBrains and located under the official installation path.
Is clion64.exe a Virus or Malware?
The real clion64.exe is NOT a virus. However, malware can masquerade with similar names; verify the path and signature.
How to Tell if clion64.exe is Legitimate or Malware
- File Location:: Must be in
C:\Program Files\JetBrains\CLion \bin\clion64.exe or C:\Program Files (x86)\JetBrains\CLion \bin\clion64.exe. Any other path is suspicious.
- Digital Signature:: Right-click clion64.exe → Properties → Digital Signatures. Should show a signature from
JetBrains s.r.o..
- Resource Usage:: Normal idle usage is 1-20% CPU per core and 150-900 MB memory. Unusually high usage when CLion is closed indicates something malicious.
- Behavior:: CLion should start when you open the IDE and stop when closed. Persistent background activity outside of CLion sessions warrants a scan.
Red Flags: If clion64.exe is found outside official JetBrains paths (e.g., AppData, Temp), lacks a valid JetBrains signature, or runs constantly without CLion being opened, scan for malware and verify the installer.
Why Is clion64.exe Running on My PC?
CLion runs to support active development, indexing for fast navigation, and background tasks such as VCS checks and code analysis once a C/C++ project is loaded.
Reasons it's running:
- Active Project Opened: CLion launches process(es) to manage the UI, indexing, and builds when a C/C++ project is loaded.
- Background Indexing: Indexing analyzes symbols, headers, and dependencies to enable quick search and code insight.
- CMake Build System: CLion uses CMake to configure and generate build files, which may spawn related processes during configuration.
- Debugger Sessions: Starting a debugging session spins up debugger subprocesses for LLDB/GDB integration.
- Plugins and Inspections: Installed plugins and code inspections run in background to provide suggestions and checks.
Can I Disable or Remove clion64.exe?
Yes, you can disable clion64.exe. You can close CLion to stop it, disable indexing, or uninstall CLion if you no longer need it.
How to Stop clion64.exe
- Close CLion: File → Exit CLion or click the X button to close the IDE
- Disable Indexing: Settings/Preferences → Build, Execution, Deployment → CMake and disable automatic reindexing or adjust indexing scope
- End All CLion Processes: Open Task Manager, locate clion64.exe and related grandchildren processes, and End Task
- Prevent Startup: Disable CLion from starting with Windows via Task Manager → Startup or the JetBrains Toolbox
- Stop Background Features: Settings → Appearance & Behavior → System Settings → Background tasks, disable unnecessary background checks
How to Uninstall CLion
- ✔ Windows Settings → Apps → Apps & Features → JetBrains CLion → Uninstall
- ✔ JetBrains Toolbox (if used) → Uninstall CLion from the toolbox
- ✔ Remove remaining config directories: C:\Users\<User>\AppData\Roaming\JetBrains\CLion* and C:\Users\<User>\AppData\Local\JetBrains\CLion*
Common Problems: High CPU or Memory Usage
If clion64.exe is consuming excessive resources:
Common Causes & Solutions
- Large C/C++ projects with heavy indexing: Allow indexing to complete, or exclude large directories (External libraries, build outputs) via Settings → Editor → File Types → Excluded Files
- Background analysis and inspections: Limit inspections or adjust Code → Inspections in Settings; disable heavy rules selectively
- Insufficient memory allocated to CLion: Increase IDE heap size by editing clion64.vmoptions (e.g., -Xmx4g) in the bin directory
- Misconfigured CMake or stale cache: Reconfigure CMake: File → Settings → Build, Execution, Deployment → CMake → Reload Changes or Delete and regenerate cache
- Outdated CLion version: Update CLion to latest version via Help → Check for Updates
- Conflicting or heavy plugins: Disable or uninstall nonessential plugins via Settings → Plugins
Quick Fixes:
1. Quick Fixes:
2. 1. Close unnecessary CLion projects or suspend indexing temporarily
3. Increase heap size in clion64.vmoptions (e.g., -Xmx4g)
4. Exclude non-source directories from indexing
5. Disable unused plugins
6. Update CLion and re-run the project configuration
Frequently Asked Questions
Is CLion safe to run on Windows?
Yes. CLion is a legitimate JetBrains IDE. Ensure you download from jetbrains.com and keep it updated to receive security patches.
Why is CLion using so much CPU?
CPU spike usually happens during indexing or building large C/C++ projects. Check CLion Task Manager (Shift+Esc) to identify the culprit, then exclude paths or pause indexing.
Can I uninstall CLion without losing my code?
Yes. Uninstall CLion via Windows Settings, but your source files remain. If you use CLion’s configurations, you may back up CMakeLists.txt and .idea folders from your project.
Does CLion require internet access?
CLion itself runs offline, but some features (plugin updates, license validation, remote toolchains) may require internet access.
How do I increase the heap size for CLion?
Edit clion64.vmoptions in the CLion bin folder to increase -Xmx (e.g., -Xmx4g). Restart CLion for changes to take effect.
Where are CLion settings stored?
User-level settings are stored in your home directory under .CLion<version> (e.g., C:\Users\<User>\.CLion2025.3) and project-specific settings reside in the project’s .idea folder.