Overview

MemTest86+ is a free, open-source memory tester that boots independently of the operating system. It is best suited to users diagnosing crashes, freezes or instability who can start a computer from removable media or a network. Its focused testing and broad architecture support are useful, but Secure Boot and unfinished USB support can complicate setup.

Key features

Memory testing

MemTest86+ uses algorithms including moving inversions and Modulo-20 testing to detect memory failures. It can access almost all system memory without depending on operating-system memory management or UEFI libraries, which makes it useful when instability prevents reliable testing from within the installed OS.

Testing runs indefinitely. The pass counter advances after every selected test has completed, giving users a way to track cycles while deciding when to stop. The scope is deliberately narrow: it supports memory and stress testing, not disk health checks or GPU testing.

Boot choices and constraints

It can start through legacy or UEFI BIOS, or Linux boot protocols, and run from a FAT32 USB drive or CD-ROM. PXE network boot is also supported: memtest.bin is the BIOS PXE payload, while memtest.efi is for UEFI PXE, including iPXE or PXELINUX. These options make it suitable for both one-off checks and configured network-boot environments.

Secure Boot must be temporarily disabled because the binary is not signed by Microsoft. USB support remains a work in progress, and some devices are unsupported, so a CD-ROM or network boot may be preferable when a USB device fails. Stable binaries are available; nightly builds are automatically generated, untested and unsupported, making them a poor choice when dependable support matters.

License and support

The GNU GPL version 2 permits private and commercial use without additional restrictions beyond the license. The build is tested on Linux using the GNU toolchain, including GCC, binutils and make. The project directs bug reports to its official GitHub page and asks users to include hardware details and reproduction steps.

Pricing

Free and open-source: 0.00 USD per free. The plan includes a stand-alone memory tester under GPLv2 for private or commercial use. There is no paid tier to unlock additional test types; the trade-off is that the product remains focused on memory diagnosis rather than disk or GPU checks.

Platforms

MemTest86+ supports x86, x86-64, ARM AArch64 and LoongArch64 computers. It is listed for Linux, macOS and Windows, but runs as bootable diagnostic media rather than a conventional desktop application. Users should match the boot method and media to their system; support for a platform does not remove the Secure Boot requirement or USB-device limitations.

Who it's for

Choose MemTest86+ when you need a no-cost, bootable way to investigate suspected memory faults across supported architectures, especially when testing outside the installed OS is valuable. It is less suitable if you need a broad hardware suite, a signed binary that runs with Secure Boot left on, or assured compatibility with every USB device.

Pros and cons

Pros: Accesses almost all memory without relying on the operating system or UEFI libraries, useful when the OS may be unstable.
Pros: Supports several architectures and boot paths, including removable media and PXE.
Pros: GPLv2 allows private and commercial use at no charge.
Cons: Secure Boot must be temporarily disabled.
Cons: USB drivers are unfinished and some devices are unsupported.
Cons: It does not check disk health or test GPUs.
Cons: Nightly binaries are untested and unsupported.

Alternatives

For a wider range of hardware checks, browse Hardware Diagnostic Software. For tuning-focused options, see PC Overclocking Software.

MemTest86 is another memory-testing option, with a free edition and a paid Pro Download.
OCCT is a freemium alternative for users who want core features on its free personal plan or an unlimited test on its 4.50 EUR per month Supporter plan.
HCI MemTest is an alternative with a free Windows version and a 5.00 USD one-time Pro plan.
y-cruncher offers a free plan for non-commercial and academic use, including commercial technology reviews.
RyzenAdj is a free Linux and Windows command-line tool for a different hardware-software task.
Universal x86 Tuning Utility is a free Windows tuning utility rather than a bootable memory tester.
Intel VTune Profiler is a free profiler for Linux, Windows and self-hosted use.
Prime95 is another free alternative.

Verdict

MemTest86+ is a strong fit for users who need free, architecture-spanning memory checks from a bootable environment. Its independence from the operating system and flexible boot options are the main reasons to choose it; look elsewhere if Secure Boot must remain enabled, USB compatibility is critical, or you need disk and GPU diagnostics alongside memory testing.

	MemTest86+	ZenMaster
Free plan	Yes
Paid from	Free
Platforms	Linux, macOS, Windows	Linux, macOS, self-hosted, Windows
Free plan	Yes
Platform support	multi-platform
Stress testing	Yes
Memory testing	Yes
Disk health checks	No
GPU testing	No
Bootable diagnostic media	Yes
CPU tuning		Yes
Hardware scope		amd

MemTest86+ vs ZenMaster

MemTest86+

ZenMaster