The Chrome Extension Side Hustle Nobody’s Talking About
Everyone’s fighting over the same saturated markets. I found a smarter angle: expired Chrome extensions with proven user bases and zero active competition.
Everyone’s building new Chrome extensions. I’m making money from dead ones.
Here’s the underground strategy that’s generating consistent side income while everyone else fights in saturated markets, and why almost nobody is talking about it yet.
TLDR;
Indie makers and vibe coders looking for a validated, profitable idea should consider the Chrome Goldmine, a new database of expired Chrome Extensions that can easily be rebuilt for an existing userbase.
Instead of a complex SaaS that takes months to build, consider these browser extensions a micro-SaaS or even a starting point for one. Several case studies of extensions that became million-dollar companies are included in the database.
As one reader said:
Chrome extensions are like the gateway drug for indie makers. Low overhead, quick to launch, and you can test ideas fast. Plus, if it flops, you only wasted a few weekends.
1 AM, Five Failed Hustles, and a Stupid Amount of Tabs Open
It was a Tuesday night in March when I hit my personal low point.
I’m lying in bed, phone tilted at an angle that will absolutely destroy my neck, scrolling through “best passive income ideas 2025” for the fourth time that week. Not because the first three times were helpful (they weren’t) but because I couldn’t stop. Each article promised the same five things: dropshipping, print-on-demand, digital products, affiliate marketing, YouTube. Each one I’d either already tried or already written off.
Let me give you the embarrassing count: in the previous 14 months, I had started and abandoned five different side hustles. A Shopify store (failed). A newsletter (three issues in, zero momentum). A freelance writing attempt that lasted exactly one client. A Notion template shop that made $46. And a half-built SaaS that I stopped mentioning to people because the shame was too fresh.
Five. In fourteen months.
I’m not sharing that for sympathy. I’m sharing it because 72% of Americans either have a side hustle or are actively considering one, and most of them are cycling through the same exhausted playbook I was. The problem isn’t work ethic. The problem is choosing from an ocean of unvalidated ideas in markets already drowning in competition.
I kind of realized, staring at that ceiling, that I wasn’t failing at execution. I was failing at selection.
Why Every “Hot” Side Hustle Is Already Crowded
Here’s a number that should terrify you: there are nearly 3 million new side hustles launched every single year in the US alone.
Three million. Every year.
That means any market that gets mainstream attention (dropshipping, digital products, Chrome extensions) is absorbing millions of new entrants simultaneously. The advice is always the same: “find a niche,” “solve a real problem,” “validate before you build.” Great. But how? Everyone is told to validate. Nobody is told where to look.
That’s the gap I stumbled into.
The Counterintuitive Discovery
I wasn’t looking for a side hustle strategy when I found this. I was doing what I always do when I’m stuck: opening a ridiculous number of browser tabs and hoping one of them contained the answer.
Somewhere in that spiral, I ended up on the Chrome Web Store looking at a productivity extension a friend had mentioned. It had 78,000 users. The reviews were glowing. “Life-changing,” one said. Another: “Why isn’t this more popular?”
Then I noticed: last updated November 2020. Developer email on file. No active support thread. No recent responses to reviews.
Seventy-eight thousand people using a tool that had been quietly abandoned for years.
It hit me that this wasn’t a dead end, it was an open door. The market existed. The users existed. The validation existed. The only thing missing was someone paying attention.
Why Expired Extensions Are Validated Markets in Disguise
Look, I’m not going to pretend this is passive income. There’s work involved. But there’s a massive difference between working on something with proven demand and working on something you hope someone wants.
Here’s what an abandoned Chrome extension actually represents:
Real users who chose to install it (not just people who stumbled on a landing page)
Real retention: people who kept it installed even after the developer went quiet
Real reviews describing exactly what they love and what they wish were better
Real absence: an active gap where a competitor should exist but doesn’t
The Chrome Web Store currently has around 112,000 active extensions, down 18.5% since 2020 due to curation, deprecation, and abandonment. The Manifest V3 transition made this worse: Chrome disabled V2 extensions for all users by mid-2025, killing thousands of tools that developers never bothered to update.
84,000 extensions and their 426 million users are being orphaned by this shift.
That’s not a crisis. That’s a pre-built audience.
The Three Ways to Play This
Once I understood the opportunity, I found three distinct ways to act on it: each with different skill requirements and time investments.
Build the Replacement (Medium effort, highest upside)
Find an abandoned extension with 10,000–100,000 users and a clear, reproducible core function. Build a Manifest V3-compliant version. Submit it to the Store. The users searching for alternatives find you because you’re solving the exact problem the old tool solved, but you’re one of the only clean options left.
Freemium is the dominant monetization model here: free core features, paid advanced tier. Extensions like Grammarly and VidIQ have proved this model scales. For an indie hacker with a modest user base, even a $3/month freemium conversion rate at 5% across 20,000 users is $3,000/month in recurring revenue.
Compete in the Gap (Lower effort, faster to market)
Don’t rebuild the exact extension, build a better alternative positioned at the same users. Study the reviews of the abandoned tool. They’re a free research report on exactly what users wanted but didn’t get. Build that version. The incumbent is gone; you’re not fighting anyone.
Acquire the Asset (Lowest build effort, fastest distribution)
Developer emails are still on file for thousands of abandoned extensions. Many of those developers have genuinely moved on: new jobs, new projects, new lives. Their 2018 side project is a listing they forgot to check. Outreach response rates for deeply abandoned extensions sit around 25–30%, and acquisition prices are surprisingly low. You’re buying a validated user base, not a startup valuation.
The Validation Framework I Use in Under 10 Minutes
Before I invest a single hour of development time in any extension opportunity, I run it through this three-point check. This is the framework that ended my 14-month streak of launching things nobody asked for.
1. Is the demand real?
Filter for extensions with at least 5,000–10,000 users. That’s the threshold where “people installed it” stops being coincidence and starts being confirmed demand. The sweet spot for an indie approach is 50,000–500,000 users: too big to be a fluke, small enough that a scrappy V3 replacement can realistically capture a meaningful share.
2. Did they actually love it?
A 4.0+ star rating tells you the product solved the problem well. Don’t waste time rebuilding something users hated. The 1-star reviews are actually useful here too, they tell you exactly what the opportunity for improvement is.
3. Is there a vacuum?
Check the “Related” section and run a quick search for alternatives. If the alternatives section shows other deprecated V2 tools, you’re looking at a genuine vacuum. If the section shows three polished, actively-maintained V3 alternatives, move on.
The entire check takes less than ten minutes per extension when you have the right data in front of you.
My First Small Win (The One That Made It Real)
I want to be specific here because vague “success” stories are useless.
Six months after that 1 AM spiral, I identified an abandoned Gmail Pro User extension with 20,000 users and a 4.0-star rating. Last update: September 2020. The developer never bothered to adjust his extension to Manifest V3, so Google had removed it.
The core function was simple: automatically expand clipped Gmail messages, trimmed content & email threads instantly. Not revolutionary. Not AI-powered. Genuinely useful for people who use Gmail a lot (I understood the market personally, which helped).
I spent a weekend building a Manifest V3 version. It was not perfect code. It was, however, functional. I submitted it, listed it clearly as a “modern alternative” to the category, and optimized the Store listing description using the exact language from the original extension’s reviews.
Users are slowly finding their way back to this extension.
It’s not life-changing money, yet. But it’s $40/month from something I built in a weekend, that grows passively through Store search, and that required zero marketing budget.
More importantly: it’s the first thing I built in two years that I knew people wanted before I built it.
That feeling, the emotional relief of having a systematic approach instead of a prayer, is worth something I can’t put a dollar figure on.
The Shortcut I Wish I’d Had Earlier
When I first started finding these opportunities, I tracked them manually. Spreadsheets. Bookmarks. A chaotic Notion doc that I still don’t fully understand.
It was eating hours I didn’t have. I was spending more time on research than execution.
I built Chrome Goldmine because manually tracking 9,650 opportunities was eating my life. It contains every expired and abandoned Chrome extension with significant user bases, with 12 data points per entry: user count, star rating, review count, expiration reason, monetization strategy, category, estimated annual revenue potential, and more. Filter by user range, by category, by niche. Export a shortlist. Start executing.
If you want the same validated shortcut that helped me stop guessing and start executing, grab it here: https://chromegoldmine.com
It’s the difference between hoping an idea works and knowing it will.
Good luck!
Raf
That is such a clever approach to finding validated ideas! I find it really interesting because I don't know much about the extension market, but it sounds like a brilliant way to skip the "guessing" phase of building a product.
Do you think the risk of a "dead" extension being outdated technically is usually higher than the benefit of having that existing userbase ready to go?
I’ve subscribed and would be happy to support each other.
Jorrit