fish vs Zsh
Updated October 2026 · AppBreakup editorial
fish
User-friendly command-line shell with autosuggestions and syntax highlighting out of the box.
Zsh
Powerful interactive shell and scripting language, the default shell on macOS.
The short answer
Pick fish if you want autosuggestions, syntax highlighting and rich completions working the moment you install it, and you rarely need to run bash snippets as-is. Pick Zsh if you want a shell that stays mostly bash compatible and can be customised heavily through frameworks like Oh My Zsh. The key difference is POSIX compatibility: Zsh largely has it, fish deliberately does not.
fish or Zsh: our take
fish is built to be helpful without configuration. As you type, it suggests commands from history and completions, colours syntax and errors, and offers tab completions generated from man pages. Its scripting language is cleaner, with fewer quoting surprises, and a web-based page lets you set colours and prompts. Version 4 rewrote the shell in Rust. The trade-off is that fish is not POSIX compatible, so bash scripts and copy-pasted setup lines often need changes or must be run with bash, and some tools only document bash and zsh.
Zsh combines features from bash, ksh and tcsh with its own programmable completion, spelling correction, recursive globbing and shared history. It is largely compatible with bash for everyday commands and scripts, which makes switching painless, and it has been the default login shell on macOS since Catalina. Out of the box it is fairly plain; most of its appeal comes from frameworks such as Oh My Zsh and Prezto and plugins that add autosuggestions and syntax highlighting. Heavy plugin setups can slow startup, and its configuration syntax can be cryptic.
Both are free and open source, fish under the GPL and Zsh under a permissive MIT-style licence, and both run on Linux and macOS, with fish reaching Windows through WSL or Cygwin.
For someone who wants a pleasant interactive shell today and writes few shell scripts, fish gives the most for the least effort. For someone who works across many servers, follows bash-oriented documentation, or enjoys tuning their environment with a large plugin ecosystem, Zsh is the more practical choice. Many people use fish interactively and still write scripts for bash, which is a reasonable middle path.
Which should you pick?
Choose fish if…
- People who want a helpful interactive shell without spending time on configuration
- Autosuggestions and syntax highlighting with zero setup
- Cleaner, more consistent scripting language
Choose Zsh if…
- People who want a bash-compatible shell they can customise heavily
- Mostly bash compatible, easy to switch to
- Powerful completion and globbing
About each app
What is fish?
fish, the friendly interactive shell, is an alternative to bash and zsh that focuses on working well without configuration. As you type, it suggests commands from your history and completions, highlights syntax and errors in colour, and offers rich tab completions generated from man pages. It has a cleaner scripting language with fewer quoting surprises, abbreviations that expand as you type, and a web-based configuration page for colours and prompts. Version 4 rewrote the shell in Rust. fish runs on Linux, macOS, the BSDs and Windows through WSL or Cygwin, and it is free and open source under the GPL. The main trade-off is that fish is not POSIX compatible, so bash scripts and copy-pasted snippets often need changes or must be run with bash, and some tools only ship setup instructions for bash and zsh.
What is Zsh?
Zsh, the Z shell, is a Unix shell designed for interactive use that is also a capable scripting language. It combines many useful features of bash, ksh and tcsh with its own additions: a programmable completion system, spelling correction, recursive globbing, shared history between sessions, extensive prompt customisation and loadable modules. It is largely compatible with bash for everyday commands and scripts, which makes switching easy. Since macOS Catalina it has been Apple's default login shell, and frameworks like Oh My Zsh, Prezto and plugin managers such as zinit add themes and plugins for autosuggestions and syntax highlighting. Zsh is free and open source under a permissive MIT-style licence and runs on almost every Unix-like system. Out of the box it is fairly plain, so most of its appeal comes from configuration, and heavy plugin setups can slow down shell startup.
Side by side
| Attribute | fish | Zsh |
|---|---|---|
| Pricing | Open source | Open source |
| Open source | Yes | Yes |
| Self-hostable | No | No |
| Platforms | Linux, macOS | Linux, macOS |
| Best for | People who want a helpful interactive shell without spending time on configuration | People who want a bash-compatible shell they can customise heavily |
| Status | Active | Active |
Verified facts, compared
Facts both apps publish, checked on each vendor's own site.
| Fact | fish | Zsh |
|---|---|---|
| Description | Smart, user-friendly shell for Linux and macOS | Interactive shell and scripting language |
fish vs Zsh pricing
fish: open source
We couldn't verify fish's plan details on its own site yet, so we don't list them.
Zsh: open source
We couldn't verify Zsh's plan details on its own site yet, so we don't list them.
Platforms
| Platform | fish | Zsh |
|---|---|---|
| macOS | ||
| Linux |
fish facts
4 of 4 verified- Description
- Smart, user-friendly shell for Linux and macOS
- Checked Oct 25, 2026fishshell.com(opens source in a new tab)
- “fish is a smart and user-friendly command line shell for Linux, macOS, and the rest of the family.”
- Autosuggestions
- From history and completions
- Checked Oct 25, 2026fishshell.com(opens source in a new tab)
- “Reads Your Mind fish suggests commands as you type based on history and completions, just like a web browser.”
- Web configuration
- Yes
- Checked Oct 25, 2026fishshell.com(opens source in a new tab)
- “set your colors and view functions, variables, and history all from a web page.”
- Out of the box
- Syntax highlighting and completions
- Checked Oct 25, 2026fishshell.com(opens source in a new tab)
- “tab completions and syntax highlighting that just work.”
Zsh facts
3 of 3 verified- Description
- Interactive shell and scripting language
- Checked Oct 25, 2026zsh.sourceforge.io(opens source in a new tab)
- “Zsh is a shell designed for interactive use, although it is also a powerful scripting language.”
- Heritage
- Features from bash, ksh and tcsh
- Checked Oct 25, 2026zsh.sourceforge.io(opens source in a new tab)
- “Many of the useful features of bash , ksh , and tcsh were incorporated into zsh”
- Source code
- Mirrored on GitHub
- Checked Oct 25, 2026github.com(opens source in a new tab)
- “Description: Mirror of the Z shell source code repository..”
Pros and cons of fish
- Autosuggestions and syntax highlighting with zero setup
- Cleaner, more consistent scripting language
- Web-based configuration for colours and prompts
- Not POSIX compatible, so bash scripts need changes
- Some tools document only bash and zsh setup
- Smaller plugin ecosystem than zsh
Pros and cons of Zsh
- Mostly bash compatible, easy to switch to
- Powerful completion and globbing
- Huge ecosystem of frameworks, themes and plugins
- Plain until configured
- Heavy plugin setups slow startup
- Configuration syntax can be cryptic
Other apps to consider
xonshInstead of Zsh
Python-powered shell where you mix Python expressions with ordinary commands instead of learning Zsh's syntax.
fish vs Zsh: common questions
Is fish better than Zsh?
Pick fish if you want autosuggestions, syntax highlighting and rich completions working the moment you install it, and you rarely need to run bash snippets as-is. Pick Zsh if you want a shell that stays mostly bash compatible and can be customised heavily through frameworks like Oh My Zsh. The key difference is POSIX compatibility: Zsh largely has it, fish deliberately does not.
Is fish free?
Yes. fish is free, open-source software.
Is Zsh free?
Yes. Zsh is free, open-source software.
Is fish or Zsh open source?
Both are open source.
Which platforms do fish and Zsh support?
fish: Linux and macOS. Zsh: Linux and macOS.