The largest database against the cheapest all-in-one
ZoomInfo and Apollo are the two names most often placed side by side. They differ less in what they do than in what they cost and where their data runs out.
The short answer
You sell into North America and have a five-figure annual budget.
→ ZoomInfo
In the US the database is deeper than anyone else's. Direct dials, org charts, technology in use. That is what the product was built for, and that is where it wins.
You are a small team, want to start today, and want database plus outreach in one place.
→ Apollo
Apollo has a free tier, published pricing and sequences with a dialer built in. You need no second tool and no sales call to get going.
Your procurement or data protection officer looks closely at where data is processed.
→ Both will cost you time
Both are US vendors processing in the US. That is workable, but it means a review round and standard contractual clauses. With a European vendor that round disappears.
Your buyers are German family-owned firms with 50 to 500 employees.
→ Both will disappoint you
A precision machining shop in Swabia with no active web presence exists in both databases as a fragment at best. Legal form, register number, filed accounts and group ownership live in German registers that neither vendor reads systematically.
Direct Feature Comparison
Strengths and weaknesses based on real user experiences and data architectures.
ZoomInfo
US vendor from Washington State, publicly listed. The largest commercial B2B database on the market, sold on annual contracts to sales organisations above a certain size.
The greatest strengths
The weaknesses
Apollo.io
US vendor from San Francisco. Database, outreach and dialer in one product, with a free tier and published pricing.
The greatest strengths
The weaknesses
In-depth market analysis: Who is suitable for what?
Both answer the same question, in different price brackets
ZoomInfo and Apollo solve the same problem: you want a list of companies and people matching your criteria, with contact details attached. Industry, size, region, seniority, technology in use. Both answer that question, and in the US both answer it very well.
The difference is mostly one of price bracket and packaging. ZoomInfo sells to sales organisations with a dedicated data budget. Apollo sells to everyone else, with an entry point that costs nothing and pricing you can read without a call. Anyone who thinks of Apollo as the cheap version of ZoomInfo is not wrong about the core.
Where the quality difference actually sits
ZoomInfo spends significant effort maintaining its holdings, including phone verification and reconciliation against company filings. Apollo leans more on enrichment from its own user base: people who use the product contribute data. That explains both the size of the database and the variance in quality.
Practically: with Apollo, expect a higher share of stale addresses and budget for verification. With ZoomInfo you pay for that verification in the price.
Where both stop in the German mid-market
Take a typical target: a supplier with 180 employees, family-owned for three generations, with a website last revised in 2019. That company is fully documented in Germany, just not where ZoomInfo and Apollo look.
Its legal form, directors and shareholdings are in the commercial register. Its headcount and revenue are in the Bundesanzeiger. Its new plant is in a district authority notice and the local paper. Its new certification is on its own news page. Its opening for a maintenance manager is on a job board.
None of that is secret. All of it is public. But neither database reads those sources systematically, because both were built for a market where company data is created differently.
Data protection: the same effort either way
Both vendors process in the US. Since the transatlantic data privacy framework that is workable again, but it remains a review round: processing agreement, transfer basis, record of processing activities. If a data protection officer has a say in your organisation, plan for it.
Expect also to be asked where the contact data came from. With both vendors the answer is: from a wide range of sources, merged and enriched. That is lawful, but it is not an answer that reassures a sceptical legal department.
What you still do not know after choosing
Say you have decided and the list is built. Two hundred companies matching your criteria, with a contact and a number. The question that actually decides whether you get a meeting remains open: why should this company talk to you now?
A filter does not answer that. A filter tells you who matches your ideal profile. It does not tell you who just invested, just certified, just posted a role or just expanded a site. Those triggers are the difference between a first call that sounds like advertising and one that sounds like it has a reason.
If your bottleneck is sheer contact volume in North America, take ZoomInfo. If you are starting small and want everything in one tool, take Apollo. If your bottleneck is the reason, and your buyers are in Germany, neither one solves your problem.
Neither ZoomInfo nor Apollo.io fit?
Kodo Leads is not a third database to filter. For a manageable number of companies we read exactly the sources where ZoomInfo and Apollo stop: the commercial register, the Bundesanzeiger, official notices, job postings and the company's own news page. Every statement carries the link it came from.