Head to head
Seamless.AI vs ZoomInfo
As a data enrichment API, Seamless.AI rates higher on the APIbenchmarks Index, 68.3 to 67.5, a 0.8-point gap. Here is how they compare on each criterion.
Criterion by criterion
| Criterion | Seamless.AI | ZoomInfo |
|---|---|---|
| Documentation & DX | ||
| Reliability | ||
| Ecosystem & SDKs | ||
| Accessibility | ||
| APIbenchmarks Index | 68.3 | 67.5 |
Specifications
| Seamless.AI | ZoomInfo | |
|---|---|---|
| Best for | Prospecting teams wanting UI plus API and MCP | Enterprise B2B intelligence |
| Free tier | Free plan (50 lifetime credits per third party; API eligibility unconfirmed) | No |
| Pricing | Per credit; sales-led Pro/Enterprise | Annual contract + bulk credits |
| Official SDKs | 6 languages | 3 languages |
Is Seamless.AI better than ZoomInfo?
On the APIbenchmarks Index, Seamless.AI rates higher (68.3 vs 67.5). It leads on the four weighted criteria, but price is reported separately, so the best choice still depends on your budget.
Verdict in one line
Seamless.AI leads by 0.8 points (68.3 vs 67.5) and wins 2 of 4 criteria; ZoomInfo wins 2.
Winner by criterion
| Criterion | Winner | ||
|---|---|---|---|
| Documentation & DX | 76 | 70 | |
| Reliability | 74 | 90 | |
| Ecosystem & SDKs | 68 | 72 | |
| Accessibility | 50 | 30 |
Choose Seamless.AI if… / choose ZoomInfo if…
- →documentation & dx matters most to you (76 vs 70)
- →accessibility matters most to you (50 vs 30)
- →you want a free tier to start (Free plan (50 lifetime credits per third party; API eligibility unconfirmed))
- →you need broad SDK coverage (6 official SDKs vs 3)
- →your use case matches its focus: prospecting teams wanting ui plus api and mcp
- →reliability matters most to you (90 vs 74)
- →ecosystem & sdks matters most to you (72 vs 68)
- →your use case matches its focus: enterprise b2b intelligence
Pricing side by side
- Model
- Per credit; sales-led Pro/Enterprise
- Free tier
- Free plan (50 lifetime credits per third party; API eligibility unconfirmed)
- Free$0
- ProContact sales (third-party: about $4,740-$9,000/yr for 5 users)
- EnterpriseCustom
- Model
- Annual contract + bulk credits
- Free tier
- No
- ZoomInfo Lite$0
- Professional~$14,995/year
- Advanced~$24,995-$30,000/year
- Elite$39,995+/year
- Enrichment API (HubSpot Marketplace)from ~$5,000/year
- Full Prospecting / Enterprise APIfrom ~$50,000/year
Vendor-published pricing, verified 2026-10-07 (Seamless.AI) and 2026-06-27 (ZoomInfo).
SDK and language coverage
Both · 0
None
Only Seamless.AI · 6
REST API (v1/v2)OpenAPI YAML/JSONPostman collectionMCP servercurl, Python and Node examplesNo official language SDKs found
Only ZoomInfo · 3
Python (official zi_api_auth_client, MIT)Java (PKI auth library)NodeJS (PKI auth library)
Strengths and weaknesses
- +Modern async API with webhooks or polling plus OpenAPI YAML/JSON specs
- +MCP server with 57 tools documented for Claude, Cursor, VS Code and ChatGPT
- +Published rate limits and simple credit rules (search 1 credit per 10 results; polling free)
- –Plan eligibility for the API is unclear and sources conflict
- –60 requests/min per endpoint, restrictive for bulk jobs
- –Pro and Enterprise pricing is sales-led
- +Deepest enterprise B2B database among enrichment APIs: ~321M+ contacts across 104M+ companies with strong direct-dial and mobile phone coverage
- +Excellent accuracy and coverage for US/North American enterprise contacts (VP+ at 200+ employee firms)
- +Asynchronous Scaling APIs with webhook callbacks handle large batch enrichment jobs cleanly
- –Opaque, sales-gated pricing with five-figure annual minimums (~$50K/year for the full API)
- –Coverage and accuracy drop sharply outside the US/Canada
- –Data freshness is cycle-based (~90-day validation refresh), not real-time, leading to email bounces in cold outreach
Seamless.AI vs ZoomInfo: questions
- Which has better documentation, Seamless.AI or ZoomInfo?
- Seamless.AI scores higher on documentation and developer experience: 76 vs 70 out of 100.
- Which is more reliable, Seamless.AI or ZoomInfo?
- ZoomInfo scores higher on reliability: 90 vs 74 out of 100.
- Do Seamless.AI and ZoomInfo have a free tier?
- Seamless.AI: yes (Free plan (50 lifetime credits per third party; API eligibility unconfirmed)). ZoomInfo: no free tier.
- How are Seamless.AI and ZoomInfo priced?
- Seamless.AI: Per credit; sales-led Pro/Enterprise. ZoomInfo: Annual contract + bulk credits.
- Which has more official SDKs?
- Seamless.AI lists 6 official SDKs, ZoomInfo lists 3.