PeakEater

6/5 For Linux users and open-source fans, PeakEater is the one I point to. It is a community-developed waveshaper with six clipping curves (Hard, Quintic, Cubic, Tangent, Algebraic, and Arctangent), and it is one of the few quality clippers that ships in VST3, AU, LV2, and CLAP across Windows, macOS, and Linux. It is a clean tool with no analog coloring, which is the point. On hard clip, it does nothing below the threshold, so it is a peak ceiling you can trust.

The resizable interface has a waveform display and a dry/wet knob, and that blend control makes it handy for parallel clipping or as a rough exciter. The look reminds me of the default Reaper plugins, for better or worse. The current release moved its oversampler from an IIR to an FIR design, which cleans up the resampling at the cost of about a millisecond of latency at 32x. That is a fair trade for the improved sound, and it also fixed an older comb-filtering bug in the dry/wet path.

The main issue is that there is no AAX build, so Pro Tools users are out. Also, because it is purely digital, you will not find warmth here unless you lean on the blend knob. And it is a one-person project, so updates arrive when they arrive. Best for: Linux and CLAP setups, and anyone who wants a transparent, verifiable peak ceiling for free. Digital, 6 algorithms · Windows, macOS (universal), Linux · VST3, AU, LV2, CLAP · up to 32x oversampling.

Verdict: the best free open-source clipper, and the one to grab if you are on Linux.