List a project

A buyer's guide to browser extension acquisitions

Browser extensions are a different beast from SaaS. Here is what I look for when evaluating a Chrome Web Store acquisition or a half-built Firefox add-on.

I have a soft spot for browser extension listings. They show up on Failedups in a steady trickle, usually priced way below their SaaS cousins, and the good ones are quietly profitable little machines. If you are thinking about a browser extension acquisition as your first micro-acquisition, the math can be friendlier than buying a half-built SaaS. The traps are different though, so let me walk through how I evaluate them.

Why this niche is interesting

A typical extension that does one job well costs almost nothing to keep alive. No servers if it runs entirely in the browser, no support email avalanche, no SOC2 nonsense. Once it is in the Chrome Web Store, you have a captive distribution channel that keeps pushing updates and discovery to users who have already granted you permission to run on their pages.

That permission is the moat. Getting a user to install something is hard. Getting them to uninstall something they vaguely remember installing is even harder. Healthy extensions in productivity, dev tools, or accessibility categories often hold users for years.

The other reason I like the category: pricing on Failedups for extensions tends to sit between $300 and $3k for half-built ones, and $5k and up for the ones with real paying users. If you are testing the waters of acquisition entrepreneurship, that is a forgiving range.

What makes a good acquisition target

When I get pinged about a buy chrome extension listing, here is the checklist I run.

  • Active install base over total installs. A 50,000 install extension where only 4,000 users have it enabled this week is worth less than a 12,000 install extension with 9,000 weekly actives. The Chrome Web Store dashboard separates these. Ask the seller to share a screenshot.
  • Low churn category. Productivity tools, developer utilities, accessibility helpers, niche workflow extensions. People install these once and forget about them in a good way. Avoid anything that lives or dies by a viral moment.
  • No fragile API dependencies. If the extension scrapes LinkedIn or rides on top of an undocumented Notion endpoint, every Tuesday is a coin flip on whether it still works. The best targets read and modify the page DOM, full stop, with no third party sync that can break overnight.
  • Reasonable permission scope. Extensions that only need activeTab or a single host permission are easier to maintain and easier to grow. Users actually read the install warning, and “this extension can read all your data on every website” is a conversion killer.

Red flags that should slow you down

Some listings look great on paper and turn into a six month rebuild project. Watch for these.

  • Saturated categories. Ad blockers, password managers, screenshot tools. The top three apps in those categories own everything, and a half-built challenger is not going to dent that.
  • Manifest V2 holdouts. Google fully retired V2 in 2024. If the extension was built before that and has not been migrated, you are buying a rewrite, not an extension. Every background page, every chrome.extension call, every persistent listener needs revisiting for service workers.
  • Reliance on undocumented browser APIs. I have seen extensions lean on private Chrome flags or experimental APIs that were never meant to be stable. Those break on every other Chromium release.
  • Aggressive permission requests. If the manifest asks for <all_urls> plus webRequest plus cookies plus tabs, the install funnel is bleeding 60 percent of interested users on the warning screen. You can sometimes shrink the permission set, but it is real work.

The Chrome Web Store ownership question

Here is the part that surprises most first time buyers. You cannot transfer a Chrome Web Store listing between developer accounts directly. Google offers no “change owner” button. The workarounds buyers and sellers use:

  1. The seller adds you as a co publisher to a Group Publisher account, then steps back. This is the cleanest path and what I recommend.
  2. The seller transfers the entire developer account credentials over. Risky, because it ties to a Google identity, and Google may flag the change.
  3. You publish under your own account using the existing source code, and the seller delists their version. You lose the install base.

For option 1, you also need to verify domain ownership for the listing’s associated website. If the seller never linked a domain, you can add one during the handover. Document this in the deal so it is clear who owns the domain on the day money changes hands.

The Manifest V3 migration tax

I budget about 40 to 100 hours of dev work for any pre-2024 extension to get fully V3 compliant and clean. Service workers behave differently from background pages. Remote code execution is gone. The chrome.scripting API replaces older injection patterns.

If the seller says “it works fine on V3, I migrated last year,” ask to see the manifest.json. The version field tells you. The presence of service_worker instead of background.scripts tells you. A host_permissions block separated from permissions tells you.

The manifest.json is the single best predictor of technical debt. Read it before anything else.

Valuation rules I use

I value extensions on monthly active users, not total installs. Total installs is a vanity number that includes everyone who tried it once in 2021.

For a profitable extension with a paid tier or freemium upsell, $1 to $3 per active monthly user is the range I see clearing. So an extension with 8,000 weekly actives and a small paid plan tends to fetch between $8k and $24k depending on growth and category. Free extensions with no monetization path are worth far less, usually a few hundred to a couple thousand, priced more on the install base as a marketing asset.

Half-built extensions with no users are valued like any half-built product, on replacement cost minus stale discount. The framework I wrote up in the stalled startup valuation post applies cleanly.

A short closing thought

Browser extensions are one of the few software categories where a solo buyer with weekend hours can run a portfolio of three or four small products without anything melting. The maintenance load is real but bounded. The distribution is built in.

If this kind of thing interests you, the extension listings on Failedups tend to move quickly. Set an alert and watch for a few weeks before bidding on anything. Patterns are easier to spot once you have read 20 of them.