SHA-256 & MD5 Checksums (verified against the official mersenne.org packages)
The checksums below were verified against the official release packages published by GIMPS at mersenne.org. Compare the SHA-256 of your downloaded file with the value listed for its package before unzipping or running the application.
Cross-Platform SHA-256 Reference Database
SHA-256: 4ce2377e03deb4cf189523136e26401ba08f67857a128e420dd030d00cdca601
MD5: 83481a73b8d6a3322d1f710bb7597b29
SHA-256: a77c9297bd80dffcb7e2e7e6e89db674126c06a2fe8e769dcec06da2e66e8516
MD5: 52e4620151b6992c8139b57e55f416bd
SHA-256: 3e5a05b1849b501e35f9def0b6c7253a13a3baafa054aa1c69ba41c1d3d3326a
MD5: 820167eeea2b5468a6a16a08ad3b26ff
How to Safely Extract & Initialize Prime95
Prime95 is a completely portable system application that requires no complex internal installer scripts. Follow these clean unzipping steps to prevent file deployment blocks or system permission crashes.
Secure Unzipping Extraction
Create a clean dedicated folder on your primary drive partition (e.g., C:\Prime95\). Extract the entire contents of your downloaded archive file straight into this file block directory paths. Do not attempt to execute files inside the zipped container.
Run the Executable
Double-click prime95.exe to run it. Prime95 is portable: no installation and no administrator rights are required.
Initialize Stress Profiles
Upon first boot window launch, click the “Just Stress Testing” option button panel. Go straight to the drop-down menu navigation path Options > Torture Test to choose your preferred processing compute load preset configurations.
If Your Browser or Antivirus Flags the Download
Prime95 is distributed as plain zip archives, so a browser or antivirus tool may occasionally show a warning about a file that is not commonly downloaded. If your browser or antivirus flags the download, do not bypass the warning. Compare the file’s SHA-256 with the official checksums on this page, or download directly from mersenne.org instead.
Download & Deployment FAQ
Got questions about our file distributions? Review the technical FAQs below regarding file packages, system options, and file sources.
Are these download links official and safe?
The primary download buttons on this page link to the official Prime95 release files hosted by GIMPS at mersenne.org. A clearly labeled Terabox mirror is also provided as a backup channel. Prime95.xyz is an independent documentation site; we do not add installer wrappers, telemetry, or bundled software components to these packages.
When should I use the 32-bit (x86) legacy version?
You should only use the x86 32-bit archive package if you are running diagnostics on legacy platforms (e.g., Windows XP or Windows 7 32-bit) or vintage computing architectures. Modern environments like Windows 10 and Windows 11 require the 64-bit deployment package to properly address system memory pools and map modern instruction extensions.
Is the full application source code available for download?
Yes. The majority of the core engine source code, written primarily in heavily optimized assembly language matrices, is open to inspection. If you wish to review or compile custom binaries, you can download the development source tree packages straight from the official GIMPS software code repositories under their dedicated license parameters.
How can I update my local version of Prime95?
Because the application operates entirely as a standalone portable package, there is no automatic updater tool. To update your client, simply download the latest stable archive version from our platform, shut down your active client, and move your existing local.txt and prime.txt files into the new directory to preserve your preferences.
Before You Run: Hardware Readiness & Environmental Pre-Checks
Prime95 is not a standard gaming application; it generates computational loads that can expose even microscopic hardware flaws instantly. Verify these three critical environmental parameters before clicking the executable binary to ensure a safe baseline evaluation.
Thermal Dissipation Overhead
Ensure your CPU cooler (AIO liquid assembly or heavy dual-tower air cooler) is properly seated with fresh, high-performance thermal paste. On CPUs that support AVX-512, these routines draw very high power and can push a factory stock cooler to its thermal limit quickly, so monitor temperatures closely.
BIOS Power Limit Verification
Check your motherboard BIOS settings. Unlocked power configurations (such as infinite PL2 limits) can force unsafe current draw through your VRMs during Small FFT tests. Consider enforcing official Intel or AMD power limits for your initial run.
Close Mission-Critical Work
Because severe hardware instability under mathematical load can trigger instantaneous Blue Screens of Death (BSOD) or hard system lockups, ensure all background work, open browser sessions, and unsaved files are entirely closed out.
Legacy Builds & Non-AVX Historical Packages
Depending on your targeted system configuration, microarchitecture age, or custom thermal benchmarking bounds, executing older iterations of the Prime95 compiler might be structurally necessary.
Prime95 v26.6 Deployment
Pure SSE2 OnlyVersion 26.6 is widely recognized across overclocking networks as the definitive build that does not execute automated Advanced Vector Extensions (AVX) workloads. This creates a realistic real-world temperature environment to isolate core clock tolerances on vintage and modern CPUs alike.
Prime95 v29.8 Deployment
AVX2 / FMA3 ReadyVersion 29.8 represents a stable platform milestone implementing heavy AVX2 vector tuning parameters while avoiding modern scheduler conflicts seen on hybrid performance/efficiency architectures. See the version history page for how this release compares with the current build.
Ready to Deploy Your First Torture Test Matrix?
Don’t launch testing parameters on an unprepared system. Download the official package file above, review your environmental cooling bounds, and initialize hardware stress analysis routines.