Enable the Develop menu in Safari on Mac

You've opened Safari to do some web work and the Develop menu isn't there. Apple hides it by default because most people never need it — but one checkbox in Safari's Advanced settings brings it back, and with it the Web Inspector, Responsive Design Mode, cache controls, and remote device debugging. Here's how to turn it on for good, on any Mac running macOS 13 or later.

Turn it on in Safari's settings

1. Open Safari and choose Safari → Settings from the menu bar, or press Cmd+,.
2. Click the Advanced tab.
3. Tick the checkbox at the very bottom. On macOS 14 Sonoma and 15 Sequoia it reads Show features for web developers; on macOS 13 Ventura and earlier it reads Show Develop menu in menu bar. Same setting, reworded between versions.

The moment you tick it, a Develop menu appears in the menu bar between Bookmarks and Window. There's nothing to save or restart — it's live. Unticking the box removes the menu just as cleanly, so there's no downside to leaving it on while you work and hiding it later.

Do it from the Terminal

If you're setting up a new Mac or scripting a machine, the same switch is a single command:

# Show Safari's Develop menu
defaults write com.apple.Safari IncludeDevelopMenu -bool true

# Undo — hide it again
defaults write com.apple.Safari IncludeDevelopMenu -bool false

Quit Safari fully with Cmd+Q first, then reopen it so the change is picked up. One caveat worth knowing: on recent macOS, Safari's preferences are protected, so Terminal needs Full Disk Access (System Settings → Privacy & Security → Full Disk Access) for the write to take effect. If the command runs without error but the menu never appears, that's the reason — the Settings checkbox above always works and needs no permissions.

What the Develop menu unlocks

Once it's showing, the menu is the front door to Safari's whole developer toolkit:

• Show Web Inspector (Cmd+Opt+I) — inspect any element, read the JavaScript console, and watch network requests.
• Enter Responsive Design Mode (Cmd+Opt+R) — preview a page at iPhone, iPad, and custom widths.
• User Agent — report a different browser to a site that gates content by browser.
• Empty Caches (Cmd+Opt+E) — force the next load to fetch everything fresh.
• Connected devices — debug Safari running on an iPhone or iPad plugged into your Mac.

That's the reason to enable it once and forget about it: every other Safari developer feature lives behind this one menu.

Keep it fast the next time

With the Develop menu showing, Empty Caches becomes your first move whenever a change won't appear. If Safari is dragging even after that, a deeper clear-out helps — see how to clear Safari website data on Mac.