7 BuiltWith Alternatives for Finding Your Next 100 Customers

If you're building a SaaS product, you already know the struggle: finding companies that actually need what you're building. BuiltWith has been the go-to for years, but let's be honest-it's expensive and often overkill for indie hackers just trying to find leads.

The good news? There are better alternatives that can help you identify companies using your competitors' products, spot churn opportunities, and build targeted prospect lists without breaking the bank. Let's dive into seven tools that actually work for small SaaS builders like you.

Bloomberry – Find Companies Using Non-Web Tools (Your Competitors Probably Can't)

Here's the thing about BuiltWith: it only sees what's on a company's website. But what if you're building something that competes with tools like Microsoft Teams, Figma, or Linear? These products don't leave footprints on company websites, which means BuiltWith can't help you find users.

That's where Bloomberry comes in.

Let's say you're building a video conferencing tool. You search for "Zoom" in Bloomberry and suddenly you've got a list of 15,000 companies using it-complete with employee counts, revenue estimates, and industry classifications. Now you've got a targetable list of companies that clearly have a need for video solutions. Try that in BuiltWith and you'll come up empty because Zoom doesn't embed anything on company websites.

Or maybe you're building a design collaboration tool. Search for "Figma" and Bloomberry shows you thousands of companies using it, along with when they started their subscription. You can filter for companies in your target market-say, agencies with 10-50 employees-and export a list ready for outreach.

The churn detection is where things get spicy. Bloomberry can tell you when companies stop using a product. I searched for companies that recently dropped Zendesk and found dozens of businesses in the market for a new support solution. If you're building a helpdesk tool, these are leads that are already looking for alternatives. They're not happy campers, and they're actively evaluating new options.

Here's another angle: Bloomberry shows you companies using multiple complementary tools, which helps you understand their tech ecosystem. For instance, if someone uses both Notion and ClickUp, they're probably power users who care deeply about productivity tools. That's valuable context you can't get from BuiltWith's website-scraping approach.

The catches? Bloomberry doesn't track frontend frameworks well. Need to find React or Vue.js users? BuiltWith has 53M+ companies; Bloomberry has zero. Also, if you need massive lists of Shopify or WordPress sites, BuiltWith still wins on sheer volume. But for finding users of SaaS products like Slack, Notion, or HubSpot? Bloomberry crushes it.

Paid plans start at $199/month with both UI and API access. Not cheap for solo builders, but if you land even one customer from it, it pays for itself. Check it out at bloomberry.com.

Aomni – When You Need More Than Just Tech Data

Okay, so Aomni isn't exactly like the other tools on this list. It's less "here's a list of companies using X" and more "here's everything you need to know to close this deal."

If you're at the stage where you're doing outbound sales and need to research accounts deeply before reaching out, Aomni is worth looking at. It's an AI platform that combines tech stack analysis with account research, so you're not just finding leads-you're understanding them.

What you get: AI-powered research on prospects (beyond just their tech stack), account mapping and planning tools, help prepping for sales calls based on what tech they use, and an AI chat interface for digging into accounts.

Honestly? This is overkill if you're just validating your idea or doing early-stage cold outreach. But if you're selling to enterprises or doing strategic account-based sales, and you need to deeply understand each prospect before reaching out, Aomni can save you hours of manual research.

It's more of a "sales intelligence platform" than a simple tech lookup tool. Price-wise, it's geared toward established startups with revenue, not day-one builders. But if that's you, check out their website technology checker at aomni.com to see if it fits your workflow.

SimilarWeb – Tech Stack + Traffic Data = Better Targeting

SimilarWeb is interesting because it gives you tech stack data PLUS traffic analytics. This combo is actually super useful when you're prioritizing which companies to reach out to.

Let's say you find 1,000 companies using your competitor. Which ones do you email first? SimilarWeb shows you traffic data, so you can target high-traffic sites first (they probably have budget) or low-traffic sites (they might be easier to convert).

You can also see what percentage of companies in your space use certain tools. If 60% of fintech companies use Stripe but only 10% use your competitor, that tells you something about market saturation and your positioning.

Track when competitors add or remove technologies. If you notice a competitor swapping analytics tools or payment processors, that might signal issues you can capitalize on in your messaging.

SimilarWeb isn't cheap, and it's probably overkill if you're just trying to find your first 10 customers. But if you're doing competitive research and want traffic data alongside tech intel, it's one of the few tools that combines both.

Hunter TechLookup – Best Free Option for Bootstrappers

If you're bootstrapping and not ready to drop $200/month on lead gen tools, Hunter TechLookup is your best bet. The free tier is actually usable (5,000 websites per search), and it's made by the same team behind Hunter.io-the email finder tool you're probably already using.

The free plan gives you the first 5,000 websites in any search. That's not a trial or a tease-that's a real product you can use to build your first prospect list without paying anything.

Here's the magic combo: Use TechLookup to find companies using your competitor's product, then use Hunter.io to find the decision-maker's email. Export the list, verify emails in Hunter, and you've got a complete outbound campaign ready to go.

No overwhelming dashboards or enterprise features you'll never use. Search for a technology, filter by category or language, see the results. That's it.

The workflow: Search for your competitor's product (e.g., "Intercom"), filter by company size or industry if needed, export up to 5,000 websites for free, use Hunter.io to find contact emails, then start reaching out.

Premium plans go up to 50,000 websites, but honestly, if you can't convert customers from 5,000 qualified leads, more data isn't your problem.

Bonus: Hunter has Chrome/Firefox extensions, Google Sheets add-ons, and Gmail automation. It's basically built for indie hackers who need to move fast without building their own sales stack.

Wappalyzer – Quick Research While Browsing

Wappalyzer is a browser extension that tells you what tech any website uses, right as you're browsing. It's not a lead gen tool-it's more for quick competitive research or validation.

Browsing a competitor's site? Click the Wappalyzer icon and instantly see their entire stack: what CMS they use, their analytics tools, payment processor, email provider, everything. Great for understanding how they built their product.

If you're trying to figure out your ideal customer profile, Wappalyzer helps you spot patterns. Browse 20 sites in your target market and take notes on what tech they use. You might discover that "companies using Webflow + Stripe + Segment" is your perfect ICP.

Sometimes you stumble onto a cool site and wonder how they built it. Wappalyzer satisfies that curiosity instantly-and sometimes you discover tools you didn't know existed.

What it detects: CMS platforms (WordPress, Shopify, Webflow, etc.), JavaScript frameworks (React, Vue, Next.js), analytics and marketing tools, eCommerce platforms and payment processors, CDNs, fonts, hosting providers.

It only works one website at a time. You can't export lists or search for "all companies using X." For that, you need one of the other tools on this list. But as a free browser extension for quick research? It's essential. Install it on Chrome, Firefox, or Edge and it's ready to go.

WhatRuns – Wappalyzer's Lighter Alternative

WhatRuns is basically Wappalyzer's younger sibling-same concept (browser extension that detects tech), but with a slightly different approach.

Here's something unique: You can "follow" websites and get notified when they change their tech stack.

Why does this matter? Let's say your competitor just launched and you want to know when they switch from their MVP stack to production tools. Or maybe you want to track when companies in your space adopt new technologies. WhatRuns will ping you when changes happen.

Sometimes WhatRuns catches things Wappalyzer misses, and vice versa. If you're serious about understanding a competitor's stack, install both and compare. They occasionally disagree on framework versions or miss different third-party scripts.

The setup: Install the WhatRuns extension from Chrome Web Store, visit any website, click the WhatRuns icon (turns blue on active sites), browse the sidebar showing all detected technologies, click any technology for detailed explanations.

Use this alongside Wappalyzer for cross-validation. When building your own product, understanding the "standard stack" for your niche helps you make better technical decisions and communicate better with potential customers who ask about your tech choices.

Lead411 – When Email Finding Is Your Priority

Lead411 is less about tech detection and more about turning those tech insights into actual conversations. It combines basic tech stack data with powerful email finding and verification.

Dead emails kill outbound campaigns. Lead411 verifies emails in real-time, so you're not wasting time on bounces. For bootstrappers doing high-volume outreach, this is huge.

Filter by specific industries to focus on your niche. Building a tool for real estate? Healthcare? SaaS? Lead411 lets you drill down fast instead of sorting through thousands of irrelevant companies.

Even if you're a solo founder, the team collaboration features help if you bring on a VA or cofounder later. Share lists, track who's reaching out to whom, organize leads across different campaigns.

Lead411 automates a lot of the manual work: Search by technology + industry + company size, generate targeted lead list automatically, get verified emails for decision-makers, export and start your outreach campaign.

Pricing: Free 7-day trial to test it out, Basic Plus Unlimited at $99/month/user, and Enterprise with custom pricing. For most indie hackers, the trial is enough to build a solid initial prospect list. If you convert a few customers, the paid plan might be worth it, but you can also just run periodic trials to build lists when you need them.

Which Tool Should You Actually Use?

Here's my honest take as someone who's been in the trenches:

If you're pre-revenue and bootstrapping: Start with Hunter TechLookup (free) and Wappalyzer (free). That combo gives you lead lists and competitive research without spending a dollar.

If you're finding product-market fit: Add Bloomberry ($199/mo). Being able to find users of non-web tools is a game-changer that BuiltWith can't match. If you close even one $1k/year customer from it, it's paid for itself.

If you're doing competitive analysis: Install WhatRuns alongside Wappalyzer. Cross-reference their findings and track when competitors change their stack.

If you're doing high-volume outbound: Lead411's email verification and industry filtering will save you hours of manual work. The trial alone might get you 50-100 qualified prospects.

If you need traffic data too: SimilarWeb is expensive but powerful. Only worth it if you're prioritizing leads by traffic/engagement metrics.

If you're selling to enterprises: Aomni makes sense when you're doing strategic, high-touch sales and need deep account research beyond just tech stack.

The truth? Most indie hackers should start with the free tools (Hunter TechLookup + Wappalyzer + WhatRuns) and only upgrade to paid options once they've validated their outreach actually works. Don't optimize lead generation before you've proven you can close deals.

Now go find those customers.