clpeak

clpeak is a cross-platform benchmark for comparing CPU, GPU and NPU performance through the APIs those devices actually expose. It is aimed at developers, hardware evaluators and technically minded buyers who need repeatable measurements rather than a single composite score. Its open-source breadth and command-line control are persuasive, although unsigned desktop binaries make the first launch less convenient.

Overview

The software measures compute throughput, memory bandwidth, matrix throughput, kernel-launch latency and AI inference. By running the same test families through available device APIs, it can put results from different machines side by side. That is useful when assessing an accelerator in a particular software stack, or when checking whether a processor delivers the performance expected from its specifications.

Comparisons are only as consistent as the hardware and APIs present on each system. Missing backends or devices mean that two machines may not expose identical datapoints, so clpeak suits controlled technical comparisons better than casual “which PC is faster?” browsing.

Key features

Benchmark coverage includes general compute, matrix engines, vendor libraries, bandwidth, latency, AI workloads and CPU-specific operations. GPU backends span CUDA, ROCm/HIP, Metal, oneAPI/SYCL, Vulkan and OpenCL, while AI runtimes include ONNX Runtime, Core ML and LiteRT. This range is valuable for mixed hardware fleets: users can target the interface relevant to a particular GPU, NPU or operating system instead of relying on one generic workload.

The app detects available devices, streams measurements as they are produced and retains run history. Runs can be renamed and exported as JSON, which makes it practical to archive results or feed them into another reporting workflow. The command-line interface goes further: it can select devices, backends and test categories, explain what measurements mean, save runs as JSON and compare them with saved runs. Those controls make clpeak a stronger choice for repeatable and automated benchmarking than a one-click score utility.

Pricing

clpeak is free software under the GPL-3.0 license. The Free plan costs nothing and has no trial or subscription terms. There is no paid tier that adds seats, quotas or expanded exports; every user receives the same app and CLI distribution. That is an excellent fit for laboratories, developers and enthusiasts who can manage their own result storage and interpretation. Readers wanting a hosted comparison service or polished commercial support should consider a different tool.

Platforms

Releases support Windows, macOS, Linux, iOS and Android. Download packages include the CLI and app, backend variants and a macOS DMG; Linux users can also install through Snap, and Android users can obtain the app through Google Play. Windows and macOS binaries are not signed with a developer certificate, so those systems warn before first launch. That prompt is a security step users must handle themselves, and it is the main distribution friction.

For bug reports, the project asks users to open a GitHub issue and attach verbose run diagnostics. This process is appropriate for an open-source project, but it is less immediate than commercial vendor support.

Who it's for

Choose clpeak if you compare systems across operating systems, need visibility into several accelerator APIs, or want benchmark jobs that can be scripted and exported. Developers validating CPU, GPU or NPU performance will benefit from selecting exact devices and backends. Hardware buyers can use its workload-specific results when a headline score would hide memory, matrix or latency behavior.

It is less suitable for readers seeking a simple consumer ranking, a built-in online comparison database or a signed installer with guided support. Its output rewards users who understand which APIs are active and how to interpret differences between runs.

Pros and cons

Pros

• Broad hardware coverage: CPU, GPU and NPU measurements span compute, bandwidth, matrix, latency and AI workloads.
• Many backends: CUDA, ROCm/HIP, Metal, oneAPI/SYCL, Vulkan, OpenCL and three AI runtimes accommodate varied hardware stacks.
• Automation-ready: The CLI selects devices and tests, saves JSON and compares previous runs.
• Open-source pricing: GPL-3.0 software costs 0.00 USD, with no trial expiry or paid feature split.

Cons

• API-dependent comparisons: Different machines may expose different devices or backends, limiting like-for-like results.
• Unsigned desktop releases: Windows and macOS display first-launch warnings.
• No comparison database: You must manage saved results or exports rather than browse a central catalogue.
• Technical support workflow: Bug fixes go through GitHub issues with verbose diagnostics, not a dedicated support desk.

Alternatives

CrossMark is the better pick for a freemium benchmark with a free dashboard and automatic online result submission, plus a free trial for its paid offering. Geekbench suits readers who want established CPU and GPU compute tests with online results management; its Pro edition costs 99.00 USD once per user. Choose Basemark GPU for a focused graphics benchmark and Powerboard submission, accepting that the free edition is for home or private use, requires internet and provides one score without breakdown analysis.

Novabench is a simpler desktop option covering CPU, GPU, memory and disk with online comparison. elbencho is preferable for GPL-3.0 distributed-storage benchmarking on Linux and Windows. Blender and DaVinci Resolve are free creative applications rather than general-purpose benchmark replacements. Nexus is another free cross-platform software option, but serves a different purpose.

For a wider catalogue of PC testing tools, see PC Benchmark Software.

Verdict

clpeak is a strong recommendation for engineers, developers and enthusiasts who need detailed, scriptable measurements across CPUs, GPUs and NPUs. Its combination of broad backends, workload depth and JSON workflows is the main reason to choose it. Look elsewhere if you want a central online ranking, a simple consumer score or signed desktop installers with commercial support.