macemu

Classic Mac software, running in your browser tab

What actually runs here, and what cannot

Short version: classic Mac OS runs — System 6, System 7, Mac OS 8 and Mac OS 9. Mac OS X and macOS do not. That line is not a matter of effort or ambition; it is a line between two entirely different computers that happen to share a brand. This page explains where it falls and why, because the question gets asked constantly and most answers on the web are either hand-waving or wrong.

The three machines on this site

Emulated machineRunsEmulatorHow it feels
Macintosh PlusSystem 1 – System 7.5Mini vMacInstant. 512×342 black and white. Runs happily on a phone.
Quadra 650 (68040)System 7 – Mac OS 8.1Basilisk IIQuick. 640×480 in 256 colours. The workhorse for most of the catalogue.
Power Macintosh G3Mac OS 8.1 – 9.0.4SheepShaverHeavier. Needed only for PowerPC-only software.

Picking the wrong machine is the most common reason a program refuses to start. Software from 1987 written for a Mac Plus will often not run under Mac OS 9; software compiled for PowerPC will not run on a 68k Quadra at all. Each title page on this site says which machine it uses and why.

Why Mac OS X is a different problem

In 2001 Apple replaced the Mac OS entirely. Mac OS X is a Unix system descended from NeXTSTEP, with a different kernel, a different API, a different binary format and — after 2006 and again after 2020 — different processor architectures. Emulating it is not an extension of emulating System 7; it is a separate project.

It has been done. The Infinite Mac project runs Mac OS X 10.1 through 10.4 in a browser using PowerPC emulators, and it is an impressive piece of work. It is also slow: minutes to boot, and sluggish once there. That is not a criticism of the implementation — a pure interpreter emulating a 1990s PowerPC in JavaScript-adjacent WebAssembly is simply working very hard.

Modern macOS on Intel or Apple Silicon is further out of reach again, and would require Apple's licence besides. If somebody promises you macOS in a browser tab, they are selling a remote desktop to a real Mac in a datacentre, which is a perfectly good product and a completely different thing.

What about a .app or a .dmg?

A .app is a folder holding a compiled macOS binary. It runs on macOS and nowhere else. No emulator on this site changes that.

A .dmg is a disk image, usually containing one of those. You can open it here and take out documents, images or data — see the DMG page — but an application inside will not run.

The files that do run here are from the earlier era: .sit archives, .hqx and .bin encoded files, and floppy or hard disk images in .img, .dsk or DiskCopy format. The loader takes all of them.

The honest limitations

Where to go for more

This site is a catalogue with an emulator attached: one page per title, built to be findable and to start in one click. If what you want is the whole machine, other projects do it better and deserve the traffic: