Arc Browser Eating Storage on Mac? How to Trim It Down

Arc’s a Chromium-based browser with a different attitude toward tabs — Spaces, pinned sites, an automatic archive, and a generally heavier UI than Chrome’s. The trade-off: Arc accumulates more local storage than typical browsers. After a few months of daily use, your Mac’s storage chart can show 5-10 GB attributed to Arc alone.

Most of that’s recoverable without losing anything you’d miss. Here’s how.

Where Arc actually stores data

Arc’s Mac data lives in a few specific places:

• ~/Library/Application Support/Arc/ — main data folder (profiles, Spaces, settings)
• ~/Library/Caches/Company.ThBrowser.Arc/ — cache (note the unusual bundle name)
• ~/Library/Containers/Company.ThBrowser.Arc/ — sandboxed data on newer versions

The biggest space-hogs inside ~/Library/Application Support/Arc/:

• User Data/Default/Cache/ — HTTP cache, can be 1-3 GB
• User Data/Default/Code Cache/ — JavaScript bytecode cache
• User Data/Default/Service Worker/ — service worker storage for PWAs and similar
• User Data/Default/IndexedDB/ and Local Storage/ — site-specific storage; web apps like Notion, Figma, Linear can hold big chunks here
• archived/ and similar — archived tab data

Open Finder, cmd-shift-G, paste ~/Library/Application Support/Arc/, and check sizes via cmd-I (Get Info) on subfolders.

The fastest way to clean: use Arc’s UI

Arc has a Clear Browsing Data dialog like its Chromium siblings. Cmd-shift-Delete opens it. Or via menu: Arc → Clear Browsing Data.

Two tabs:

• Basic — Browsing history, cookies and other site data, cached images and files
• Advanced — adds passwords, autofill, site settings, hosted app data

For storage cleanup, tick “Cached images and files” and “Hosted app data” (the latter recovers space from heavy web apps that have grown). Time range: All time. Click Clear data.

Cookies stay (so you stay signed in). History stays. The cache and big web app caches go.

Archive cleanup

Arc auto-archives tabs after a set period (12 hours, 24 hours, 7 days, etc., configurable in Settings). Archived tabs aren’t using memory but they do use a small amount of storage. After heavy use, the archive can hold thousands of entries.

To clear: Arc menu → Archive → ⌘ click on “Clear Archive” or right-click an archive entry to delete it. There’s no “delete all” button last time we checked, so bulk cleanup isn’t elegant — but the storage cost is moderate (usually under 500 MB even with thousands of entries).

To keep Arc lean going forward: Settings → adjust archive timing to a shorter period.

Service workers and PWAs

Arc’s service worker storage can balloon if you use heavy web apps. Notion, Figma, Linear, Roam, Slack web — all use service workers to cache assets and operate offline.

To check: type chrome://serviceworker-internals/ in the address bar. You’ll see every registered service worker. Click “Unregister” on ones for sites you don’t use anymore.

Or take the simpler path: clear browsing data with “Hosted app data” ticked. Service worker caches go with it.

Multiple profiles

Arc supports multiple profiles, each with its own data. Click your avatar (top of sidebar) to see profiles. Each profile has its own User Data folder under ~/Library/Application Support/Arc/User Data/.

If you’ve created and abandoned profiles (a Work profile you no longer use, a test profile from when you set up Arc), they’re still there using disk. Settings → Profiles → remove unused profiles. The data is deleted with them.

Clear caches across every browser at onceSweep clears Safari, Chrome, Firefox, and Arc caches in a single pass. Free download for Mac →

Pinned tabs and Spaces

Arc keeps state for pinned tabs and Spaces. Each Space is essentially a separate workspace with its own pinned tabs, theme, and folder structure. Five active Spaces with 20 pinned tabs each is a lot of state.

It’s not a huge storage hit (each Space is small) but if you’ve created Spaces over time and abandoned them, removing them tidies up. Right-click a Space in the sidebar → Delete Space. Confirm.

Pinned tabs that you no longer use can be unpinned (right-click → Unpin) or just closed.

Update Arc

The Browser Company ships Arc updates frequently. Old versions can have bugs that cause data growth or memory issues that newer ones fix. Arc menu → About Arc — it’ll check for updates.

Restart Arc after updating so the new version is actually running.

Reset Arc to a clean state

If Arc’s behaving weirdly and storage is wildly out of control, the nuclear option:

1. Quit Arc completely (cmd-Q)
2. In Finder, cmd-shift-G
3. Paste ~/Library/Application Support/Arc/
4. Move that folder to your Desktop
5. Reopen Arc

Arc will start with a clean slate. You’ll lose Spaces, pinned tabs, archive, history, and extensions. If that fixes the issue, you can trash the old folder. If not, drag it back.

This is overkill for most cases. Try the cache clear first.

Chrome extensions in Arc

Arc supports Chrome extensions. They install into your Arc profile and bring all the same memory and storage costs. Audit them: Arc menu → Extensions, or type chrome://extensions/ in the address bar.

Same advice as for Chrome: disable anything you haven’t used in a month. Especially heavy ad blockers, privacy stacks (multiple overlapping privacy extensions), and “site improvers.”

Activity Monitor: per-tab investigation

System Activity Monitor shows total Arc memory but not per-tab. Use Arc’s built-in equivalent: Settings or Window menu → Task Manager (or check chrome://process-internals/).

Find tabs using the most memory and either close them or reload them. A tab using 1+ GB usually has a memory leak — a reload typically clears it.

What about Boosts and themes?

Arc’s “Boosts” (custom CSS/JS injected into specific sites) and themes are tiny — nothing to worry about for storage. They’re useful customisations.

If a Boost is slow or breaking a site, disable it: arc://boosts in the address bar, or click the Boost in your sidebar to manage.

Skip the manual huntSweep finds every cache, log, and forgotten file in seconds — only removes what you OK. Download Sweep free →

When the storage is genuinely necessary

Some of Arc’s storage is doing useful work:

• The Cache makes pages faster on revisit
• Service workers enable offline mode for web apps
• Archive lets you find tabs from last week
• Spaces hold tabs you’ll come back to

Aggressive clearing means slower next-load and rebuilding state. For most users, periodic cache clearing (monthly-ish) is plenty.

A practical checklist

In order of impact:

1. cmd-shift-Delete → tick “Cached images and files” and “Hosted app data” → All time → Clear
2. Audit extensions, disable unused
3. Remove unused profiles and Spaces
4. Update Arc to latest
5. Restart Arc completely (cmd-Q, reopen)

Five minutes total. Usually recovers 2-5 GB of storage and brings memory usage back down.

Cross-browser cleanup

If you’re running Arc and Chrome side by side (some users do, for different work modes), each accumulates its own cache and storage. Chrome’s cache lives at ~/Library/Application Support/Google/Chrome/Default/Cache/, separate from Arc.

Cleaning each one through its own UI takes time. A tool that handles all installed browsers in a single scan is faster, and gives you a unified view of how much storage browsers collectively are using.

Sweep clears Arc, Safari, Chrome, and Firefox caches in one pass and surfaces the largest user-data directories so you can see exactly which browser is using the most disk. Preview before anything is removed — nothing goes without your okay.