How to Install Oh My Zsh

Updated

Oh My Zsh installs by running a single install command in your terminal, and the official entry point is the Install oh-my-zsh button on ohmyz.sh. The prerequisite is that you're working in a Zsh shell — Oh My Zsh is a configuration framework for Zsh, so it manages your existing Zsh setup rather than replacing your shell. If you only want to try it on a machine where Zsh isn't your default yet, install Zsh first, then run the Oh My Zsh installer.

What you're actually installing

Oh My Zsh is described on its own site as "a delightful, open source, community-driven framework for managing your Zsh configuration." That framing matters for expectations:

  • It is not a new shell and not a standalone program you launch. It's a layer of configuration, functions, and helpers on top of Zsh.
  • It ships batteries included: thousands of helpful functions and helpers, plus bundled plugins and themes.
  • The site states it comes with 300+ plugins and 150 themes bundled.

So the install step sets up the framework and wires it into your Zsh config; the visible payoff (prompt themes, plugin behavior) appears the next time your shell loads that config.

Before you install

Requirement Why it matters
Zsh installed Oh My Zsh configures Zsh; without Zsh there's nothing to configure
A terminal you can run commands in The install is performed by running a command, per the site's "Install oh-my-zsh now" section
Ability to edit your shell config You'll typically want to set plugins/themes after install; the framework reads your Zsh config
A shell you're willing to change If Zsh isn't your default, switching to it is a separate decision from installing Oh My Zsh

The site's install section begins "Oh My Zsh is installed by run…" — i.e., the mechanism is executing a command, not downloading and double-clicking an app. Use the command shown on the official Install oh-my-zsh page rather than a copied command from a random blog, since install scripts are exactly the kind of thing that gets altered in circulation.

Install steps

  1. Confirm Zsh is available. Open your terminal and check that Zsh runs. If it doesn't, install Zsh through your system's package manager first.
  2. Go to the official site. Open ohmyz.sh and use the Install oh-my-zsh entry point. This is the canonical source for the current install command.
  3. Run the install command shown there in your terminal. Expected result: the script fetches Oh My Zsh, places it in your home directory, and backs up or updates your existing Zsh configuration so the framework gets loaded.
  4. Restart your shell or open a new terminal tab. Expected result: your prompt changes and the framework is active. If your prompt looks identical, the config isn't being sourced yet — see the troubleshooting section.
  5. Verify it loaded. The clearest check is that your prompt reflects a theme and that Oh My Zsh's helper commands respond. If they don't, the framework isn't in your active config path.

After install: turning on plugins and themes

Installing gets you the framework; the plugins and themes are opt-in through your Zsh config.

  • Plugins: the site advertises 300+ bundled plugins aimed at making a developer's life easier. You enable the ones you want rather than all of them — enabling everything slows shell startup and can create conflicts.
  • Themes: 150 themes ship bundled. Pick one and set it in your config; the site has a Find your new theme section for browsing.
  • Community: Oh My Zsh is community-driven, and the site points to a Start contributing path if you want to go beyond using it.

A practical order: install → confirm the default prompt works → add one or two plugins you actually need → then change the theme. Changing everything at once makes it hard to tell what broke if something does.

Common snags

  • Prompt didn't change. Your shell likely isn't sourcing the Oh My Zsh config — often because Zsh isn't your active shell, or your existing config file wasn't updated/backed up as expected.
  • You're still in Bash. Oh My Zsh only affects Zsh sessions. If your terminal still launches Bash, you'll see no difference until you switch.
  • Slow shell startup. Usually too many plugins enabled at once. Trim back to the ones you use.
  • A theme looks broken. Themes can depend on fonts or terminal capabilities; try another theme to isolate whether it's the theme or your terminal.
  • Copied an install command from elsewhere. Re-run from the official site's install entry to be sure you used the current, intended command.

Who this is for

Oh My Zsh suits developers who already use (or are willing to use) Zsh and want plugins, themes, and helpers without assembling a config from scratch. If you're happy with your current shell and don't want to change your config, installing it adds a layer you won't benefit from. The site's own framing is honest about scope: it "will not make you a 10x developer" — it's a convenience and customization layer for your terminal, not a capability upgrade.