Compare software

Clock Signal vs ZEsarUX: catalog facts
Clock Signal	ZEsarUX
Free Free and open source, developed by Tom Harte.	Free Free and open source.
macOS, Linux	Windows, macOS, Linux
Emulates a wide range of 8- and 16-bit computers and consoles in one program Designed around low input and display latency	Covers every Sinclair computer Supports many regional Spectrum and ZX81 clones
No separate project homepage beyond the GitHub repository Some systems need original ROM images supplied by the user	Dense interface with many options Focused on Sinclair machines and their clones
Downloadable app	Downloadable app
Open source	Open source
License: MIT	License: GPL-3.0
No account needed	No account needed
Works offline	Works offline
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.