Side by side

Hercules vs Renode

Both stand on emulator software. Which one you can start free with, which one lets you read the code, and what each costs once you pay.

Hercules

Free plan LinuxMacWindows

Choose Hercules if you need a free emulator for IBM mainframe architectures and can provide a compatible operating system or standalone program. Look elsewhere for production-capable software or for documented support for features such as ESCON, FICON, or coupling links.

Visit Hercules

Renode

Free plan LinuxMacSelf-hosted+1

Renode combines system emulation with automation and repeatable testing across a broad set of architectures. Check its runtime requirements and available integrations against your development setup.

Visit Renode

The facts

	Hercules	Renode
Free plan	Yes	Yes
Open source	Not published	Not published
Runs on	Linux, Mac, Windows	Linux, Mac, Self-hosted, Windows
Lowest paid plan	Free or on request	Free or on request
Plans published	1	1
Maker	Not published	Not published
Website	hercules-390.eu	renode.io
On emulator software	#20 of 39	#24 of 39

Hercules: what it does well

Emulates System/370, ESA/390, and 64-bit z/Architecture.
Supports multiple legally licensed IBM operating systems.
Includes debugging tools, snapshots, and restore.
Can connect guest TCP/IP networking to the host.
Free under the Q Public Licence.

What to know first

Does not provide an operating system.
Several facilities, including ESCON and FICON, are unsupported.
The FAQ says it has never claimed production capability.
Unrestricted access to hercifc can create a security exposure.

Renode: what it does well

Free, open-source framework under the MIT license
Supports snapshots, restore, debugging, and network simulation
Runs on Windows, macOS, and Linux
Supports more than 1,200 boards, according to the project

What to know first

Requires dotnet 6.0 or later
Linux portable package requires GTK2 for the UI

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