Best 6sense Alternatives (2026)

ZoomInfo is the heavyweight champion of B2B contact databases - millions of contacts, comprehensive company data, and intent signals that can be genuinely useful for enterprise sales teams. If you work at a Fortune 500 company with a big sales org, it might be worth the investment. But here's the reality: most teams report paying anywhere from $15K to $100K+ per year, with average costs around $3,000/month and aggressive 10-30% price hikes at renewal. The contract terms are notoriously rigid with auto-renewals and a 60-day cancellation window that basically locks you in for another year if you miss it. On top of that, users consistently complain about poor data quality (company info being way off, job titles not matching LinkedIn), minimal customer support despite the massive price tag, and opaque pricing that feels designed to confuse you.

Apollo.io has become super popular in the sales world, largely because of its generous free tier that lets you dip your toes in without committing. It combines contact data with sales engagement features like email sequencing and CRM integrations, which is pretty handy for outbound teams. The free plan is legitimately useful, which is why so many people start with it. The problems start showing up when you dig deeper though - users report getting "crazy bounces" from emails Apollo claims are verified, with phone accuracy sitting at just 42% compared to the industry standard of 70%+. Email deliverability is a common complaint, with campaigns hitting spam folders or generating zero results. The pricing can also get confusing and expensive quickly, especially if you use the API heavily, and customer support is reportedly slow and unhelpful when things go wrong.

Clearbit is really powerful if you're a developer or technical team looking to enrich your customer data through APIs - they've built a solid data enrichment engine that marketing teams love for things like form fills and customer intelligence. If you're working at a well-funded company with engineering resources, it can add a lot of value. The downside? It's expensive, especially for SMBs - their Enrichment API starts at $99/month for just 275 requests, and their Prospector tool is $999/month compared to competitors charging $99 for similar features. What really frustrates users is that Clearbit charges you for every API call regardless of whether it succeeds, while competitors only charge for successful lookups. The pricing is also complex with multiple products sold separately, making it hard to understand your total cost (quotes of $20K+ aren't uncommon). Plus, it's very developer-focused with no UI for manual lookups, and it doesn't include technology profiling.

Datagma finds email addresses and phone numbers in real-time. Affordable and simple, but lacks comprehensive business intelligence and technology tracking features.

FullEnrich aggregates data from multiple sources to find emails and phone numbers with high accuracy. Great for enrichment but lacks technology profiling and business intelligence.

Kaspr is a LinkedIn extension that finds phone numbers and emails directly on LinkedIn profiles. Great for LinkedIn prospecting but limited to LinkedIn data only.

Pharow helps find professional email addresses and automate prospecting. Affordable and simple, but lacks advanced business intelligence and technology tracking.