Overview

MemTest86+ is a free, open-source utility for diagnosing system memory by booting outside the operating system. It is best suited to people tracking down crashes, freezes, or instability who are comfortable starting a PC from removable media or a network.

Its ability to inspect nearly all memory without depending on the operating system is a meaningful advantage for troubleshooting, though Secure Boot and unfinished USB support can make setup less straightforward.

Key features

Focused memory diagnosis

MemTest86+ uses algorithms including moving inversions and Modulo-20 testing to find memory failures. It runs indefinitely, with the pass counter advancing after all selected tests complete. That gives users a way to track completed cycles without imposing a fixed test duration, but someone must decide when enough testing has been done.

It is a specialist tool: memory and stress testing are supported, while disk health checks and GPU testing are not. Choose a broader diagnostic suite if you need to investigate those components as well.

Boot and architecture support

It can start from legacy or UEFI BIOS, or through Linux boot protocols, and can run from a FAT32 USB flash drive, CD-ROM, or PXE network boot. PXE setups use memtest.bin for BIOS and memtest.efi for UEFI as an iPXE or PXELINUX payload. These options suit both local troubleshooting and machines already configured for network boot.

The README describes support for x86, x86-64, ARM AArch64, and LoongArch64 systems. Although the USB route is convenient, the project's USB drivers remain a work in progress and do not support every device. The binary is not signed by Microsoft, so Secure Boot must be disabled temporarily to run it.

Release and licensing

The GNU GPL version 2 permits private and commercial use without restrictions beyond the license. Stable and nightly binaries are available, but nightly builds are automatically generated, untested, and unsupported; most users should prefer a stable build. The project asks users to submit bug reports through its official GitHub page with hardware and reproduction details.

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 weigh against it, making MemTest86+ a practical choice when a focused memory check is all that is needed.

Platforms

MemTest86+ is categorized as multi-platform and supports Linux, macOS, and Windows systems. It is not a conventional desktop application: it runs as bootable diagnostic media or through supported boot protocols. Its documented architectures are x86, x86-64, ARM AArch64, and LoongArch64.

Who it's for

Choose MemTest86+ when you need to investigate possible memory faults independently of the installed operating system, especially if you can boot from USB, CD-ROM, or PXE. It is a poor fit if you need one tool for memory, graphics, and disk diagnostics, or if disabling Secure Boot or finding a compatible USB device is not acceptable.

Pros and cons

Pros: Accesses almost all computer memory without relying on operating-system memory or UEFI libraries, useful when diagnosing system instability.
Pros: Supports several boot routes and four documented architecture families, including PXE for configured network environments.
Pros: Free for private and commercial use under GPLv2.
Cons: Requires booting separately from the operating system, rather than launching as a regular desktop diagnostic.
Cons: Secure Boot must be temporarily disabled, and not all USB devices are supported.
Cons: Testing runs indefinitely, and the utility does not check disk health or GPUs.

Alternatives

For another memory-testing option, HCI MemTest has a free Windows plan and a $5.00 USD per once MemTest Pro plan; consider it if you want a Windows program rather than a bootable standalone tester.

MemTest86 offers a free edition with no usage restrictions and a $116.00 USD per once Pro Download plan; compare it if you want to assess another product specifically named for memory testing.

OCCT has a free personal-use plan and a Supporter plan at 4.50 EUR per month. It is an option to consider if you want a broader hardware-testing product and are comfortable comparing its personal and paid plans.

Prime95 is a free alternative to consider if you are looking beyond a dedicated memory tester.

RyzenAdj is a free alternative to consider if you are comparing other system utilities.

y-cruncher offers free non-commercial and academic use; consider it if those licensing terms suit your intended use.

ASUS GPU Tweak III is another free option to consider.

Intel VTune Profiler is a free standalone tool or part of the Intel oneAPI Toolkit, with commercial and non-commercial use permitted; consider it if that profiling-tool format better matches your needs.

For wider discovery, browse Hardware Diagnostic Software or PC Overclocking Software.

Verdict

MemTest86+ is a strong choice for anyone who needs a free, focused memory diagnostic that can run outside the operating system, particularly when a bootable or PXE workflow fits the machine. Look elsewhere if you need disk or GPU checks, or if Secure Boot and USB compatibility make its boot process impractical.

	MemTest86+	ZenMaster
Free plan	Yes	No
Free trial	No	No
Paid from	Free	—
Open source	No	No
Platforms	Linux, macOS, Windows	Linux, macOS, self-hosted, Windows
Free plan	Yes	—
CPU tuning	—	Yes
Hardware scope	—	amd

MemTest86+ vs ZenMaster

MemTest86+

ZenMaster