Best B2B enrichment APIs
TL;DR
The best enrichment API depends on what you're optimizing for. Quick version:
If you want AI-native enrichment, choose MoltSets. Verified data inside Claude, Clay, Claude Code, and Codex, flat-rate from $27/mo, no per-lookup credits on emails or company data.
If you want enterprise sales intelligence, choose ZoomInfo. A full platform for contact data, intent, and prospecting workflows, quoted annually.
If you run marketing on HubSpot, consider Breeze Intelligence (formerly Clearbit). Native enrichment, lead scoring, and form shortening, included on some paid HubSpot plans.
If you want prospecting and outreach in one tool, choose Apollo. A large contact database plus sequencing and dialing on one bill, metered in credits.
If you only need work emails, choose Hunter. Domain-based discovery with verification built in, from $49/mo.
If you want fast LinkedIn reveals, choose Lusha. A Chrome extension that surfaces emails and phones as you browse, at 1 credit per email and 5 per phone.
If you're building a data pipeline, choose People Data Labs. Person, company, and IP datasets over an API, from $98/mo, billed per successful match.
If you need to unify first-party customer records, choose FullContact. Identity resolution across emails, phones, and device IDs.
The underlying trade-off: broad platforms bundle data with seats, dashboards, and annual contracts, while lean API layers give you one job done cheaply and expect you to build the workflow around them.
Why the enrichment API you choose matters
Enrichment APIs differ on fit, not just quality. Data types, verification, pricing model, and how cleanly each one slots into a workflow all vary.
Choosing wrong means paying for data you can't use. The rest of this piece segments by use case rather than naming one winner.
How we ranked these
Data types. Which fields each API actually returns: business email, personal email, mobile phone, company, firmographic, and intent data.
Verification and accuracy. How each vendor validates records, including email verification, carrier checks, source waterfalls, and stated accuracy guarantees.
Pricing model. Flat-rate plans versus credits versus volume tiers, plus lookup costs, request limits, seat minimums, contract requirements, and which fields sit outside a flat rate.
Developer experience. How fast a team gets from API key to enriched data: clear docs, an MCP server, SDKs, and no dashboard standing in the way.
Why we don't rank on database size or match rate. Vendors count records differently; some count every profile ever seen, others only verified contacts, others every identifier. Providers also don’t publish an independently audited match rate.
Best B2B data enrichment APIs compared
API | Data types | Verification method | Pricing model | Developer experience | Best for |
MoltSets | Business and personal email, mobile, LinkedIn, people and company search | Email risk scores; real-time carrier checks on mobiles | Flat-rate from $27/mo; mobile numbers metered by token; free tier available | API and MCP; no dashboard | AI-first enrichment workflows |
ZoomInfo | Contact, company, firmographic, intent | Not published | Quote-based, annual only; export credits plus seat cost | Platform-first; API access available | Enterprise sales intelligence |
Breeze Intelligence (Clearbit) | Company and contact firmographic fields | Not published | Requires paid HubSpot; limited on lower tiers; extra credits bought in packs | HubSpot-native only | HubSpot marketing operations |
Apollo | Contact email, mobile, company, intent | Not published | Credit-based, per seat; from $49/mo per seat billed annually | Full API access on Custom plans | All-in-one prospecting and outreach |
Hunter | Work email only, found and verified | SMTP checks plus confidence scoring | Credit-based, $49–$299/mo; 1 credit to find, 0.5 to verify | API, MCP, and integrations | Email finding and verification |
Lusha | Business email, phone, company, buying signals | Vendor-stated accuracy | Credit-per-reveal from a shared pool; phones cost 5x an email | API from Pro; advanced API from Premium | Fast LinkedIn contact reveals |
People Data Labs | Person, company, IP, job postings | Vendor-stated | From $98/mo, volume-tiered; overage rates depend on volume | API-first, no sales dashboard | Developer-first bulk data access |
What is the best enrichment API for AI-first workflows?
MoltSets. It provides contact and company enrichment through an API and MCP with no dashboard, so you call it directly from Claude on the web, Claude Code, Codex, Clay, or your own stack. Pricing starts at $27/mo for unlimited enrichments.
Best for: Teams that run enrichment inside AI tools for a low, fixed fee.
Pros: The MCP and API-first design fits automated workflows. Risk scores and carrier checks help you decide which contact details to use. Flat-rate access on core data makes monthly costs forecastable, and there is no per-seat pricing.
Limitations: Mobile numbers sit outside the flat rate. Each plan includes a fixed token allowance (e.g. 10 tokens on the $27 tier) and every mobile number beyond that is billed separately. There is no dashboard, sequencer, dialer, or filtered search UI.
Pricing: Paid tiers all include unlimited enrichment records on core APIs, differentiated by rate limit and included mobile tokens, and start at 27/mo. Extra mobile phone tokens are priced by tier, starting from $0.20 each at the highest volumes. Free tier available.
Verdict: Pick MoltSets if your enrichment runs through APIs or AI tools and you want a low, fixed monthly cost.
What is the best enrichment API for enterprise sales intelligence?
ZoomInfo. It combines a B2B database with prospecting, intent, and sales intelligence tooling in one platform, accessed through its own interface or API.
Best for: Enterprise sales and RevOps teams that want one system for the whole revenue org.
Pros: Broad sales intelligence capabilities across multiple prospecting tasks in one product.
Limitations: Expensive with annual contracts only.
Pricing: Usage is metered in export credits on top of the platform fee, and reported per-seat licensing runs roughly $1,500 to $2,500 per user per year on top of that. Contracts are annual with seat minimums, and there is no monthly billing option.
Verdict: Pick ZoomInfo if you want a full platform and have budget for a five-figure annual contract.
What is the best enrichment tool for HubSpot?
Breeze Intelligence (formerly Clearbit). It provides company and contact enrichment through a native HubSpot integration, so records are enriched inside the CRM rather than fetched over a standalone API.
You can enrich incoming records, score leads as data arrives, and shorten forms by filling known fields automatically.
Best for: HubSpot users who want real-time lead scoring, enrichment, and form automation without adding another tool or moving records between systems.
Pros: Enrichment sits directly in HubSpot workflows. Some credits included as part of standard HubSpot plans.
Limitations: Breeze Intelligence runs only inside HubSpot, and legacy Clearbit APIs are not available to new accounts. Not available on all HubSpot plans and additional credits need to be purchased in packs.
Pricing: Not sold standalone, it requires a paid HubSpot subscription. Credit allowances are set by your HubSpot subscription tier, with additional credits sold in packs.
Verdict: Pick Breeze Intelligence if HubSpot is your system of record and firmographic enrichment is the job.
What is the best enrichment API for all-in-one prospecting and outreach?
Apollo. It pairs a large B2B contact database with enrichment, email sequencing, and dialing in a single subscription, so the data and the outreach that uses it sit in the same product.
Best for: Outbound teams that want a contact database and a sales engagement tool together.
Pros: Prospecting data and enrichment sit in the same product ecosystem, so records move from search to sequence without an export. More affordable than ZoomInfo.
Limitations: Credit and seat-based pricing model. Full API access is reserved for Custom plans.
Pricing: Credit-based across all plans, priced per seat. Basic plan starts at $49/mo per seat when billed annually.
Verdict: Pick Apollo if you want data and outreach in one tool and your reps work inside a UI rather than a pipeline
What is the best enrichment API for verified emails?
Hunter. It finds professional email addresses by domain or person and verifies whether each address can receive mail.
Best for: Teams that need domain-based email discovery and verification and don't want to buy a broader sales intelligence platform to get it.
Pros: Email finding and verification live in one product. Developers can use the API or Data Platform, while other users connect through MCP, CRM integrations, browser extensions, or Google Sheets.
Limitations: One email found costs one credit and one verification costs 0.5 credit, so a find-then-verify workflow runs about 1.5 credits per confirmed contact. 2,000 Starter credits yield roughly 1,300 fully verified contacts, not 2,000. Unused monthly credits do not roll over, and Hunter returns email only, so phone numbers require a second vendor.
Pricing: Free includes 50 credits per month. Starter is $49 per month with 2,000 monthly credits, Growth is $149 with 10,000, and Scale is $299 with 25,000. Annual billing reduces the effective monthly price by 30 percent.
Verdict: Pick Hunter if work email is the only field you need and you want verification in the same call.
What is the best enrichment API for fast contact reveals from LinkedIn?
Lusha. Its Chrome extension reveals available business emails and phone numbers on LinkedIn profiles as you browse, with an API and MCP server available on higher plans.
Best for: Individual reps and small sales teams that prospect manually on LinkedIn and want contact details without leaving the page.
Pros: Contact discovery stays inside the rep's browsing workflow, you can reveal an email or phone without exporting a list to another tool. CSV enrichment and API access are available as you move up tiers.
Limitations: Not a full outreach suite. API access starts at Pro and advanced API features require Premium.
Pricing: Plans include a number of seats and a shared credit pool. Emails consume one credit and phone numbers consume five.
Verdict: Pick Lusha if a rep is prospecting by hand on LinkedIn and needs one contact at a time.
What is the best enrichment API for developer-first bulk data access?
People Data Labs. It supplies separate Person and Company datasets through APIs and data licensing, plus IP enrichment and job postings, with no sales dashboard in the way.
Best for: Engineering teams building custom enrichment pipelines that want to own the matching, storage, and enrichment logic themselves.
Pros: You don’t need to pay for a UI that you don’t use. You control how records are matched and stored inside your own application.
Limitations: Credit outside your plan cost extra and rates depend on your volume.
Pricing: The self-serve paid tier starts at $98 per month for Person Data beginning at 350 records, and $100 per month for Company Data beginning at 1,000 records.
Verdict: Pick People Data Labs if you have engineering capacity and want raw datasets to build on.
Frequently asked questions
What is the best B2B data enrichment API?
The best B2B data enrichment API depends on your workflow. MoltSets fits AI-first automation with flat-rate pricing from $27/mo, ZoomInfo suits enterprise sales intelligence, Hunter wins for email-only verification, and People Data Labs suits custom data pipelines. Matching the API to your use case avoids paying for features your workflow cannot use.
What makes a good enrichment API?
A good enrichment API returns the specific fields you need, tells you how confident it is in each one, prices in a way you can forecast, and integrates without a dashboard in the middle. Verification matters more than raw database size: a returned email that bounces costs you a send and a sender-reputation hit. Look for stated validation methods (SMTP checks, carrier verification, risk scores), clear documentation, an MCP server or SDK if agents will call it, and a pricing model that doesn't punish retries or failed lookups.
Which enrichment API works with Clay and Claude Code?
MoltSets works with Clay and Claude Code through its API-first, MCP-native model, so you can call enrichment inside an existing workflow instead of managing exports through a dashboard. Clay itself exposes HTTP APIs on its Growth plan and above, and several vendors in this list — including Hunter, Lusha, and ZoomInfo — now ship MCP integrations of their own.
What's the difference between contact enrichment and company enrichment?
Contact enrichment fills in details about a person: work email, personal email, mobile number, job title, seniority, and LinkedIn profile. Company enrichment fills in details about an organisation: domain, industry, employee count, revenue, location, technologies in use, and corporate hierarchy. Most workflows need both — company data to decide whether an account fits your ICP, contact data to reach the right person inside it. Vendors often price and license them separately: People Data Labs sells Person Data at $98/mo and Company Data at $100/mo as distinct products, while MoltSets includes people and company search in the same flat-rate plan.
How much does a data enrichment API cost?
Entry pricing for self-serve enrichment APIs runs from roughly $27 to $100 per month, and enterprise platforms run into five figures per year. MoltSets starts at $27/mo flat-rate, Hunter at $49/mo for 2,000 credits, Lusha at $49.90/mo list, People Data Labs at $98/mo for 350 person records, and FullContact's Acumen product at around $99/mo. Clay's self-serve Launch plan starts at $185/mo. ZoomInfo’s contracts are typically five figures annually. Most vendors also offer a free tier for evaluation, though several obfuscate contact fields on it.
How does MoltSets' flat-rate pricing compare to per-credit APIs?
Flat-rate pricing decouples cost from lookup volume. On a per-credit API, enriching 5,000 contacts costs 5,000 credits and retries cost more; on MoltSets' $27 tier the same job costs $27, capped by a rate limit of 5,000 requests per five hours rather than a credit balance. The trade-off is that mobile numbers are excluded — each plan includes a token allowance (10 on the $27 tier) and additional mobiles are billed separately, so phone-heavy workflows still carry a variable cost. Compare on your actual field mix: flat-rate wins clearly on email and company data at volume, and the gap narrows the more mobile numbers you need.
Which enrichment API fits my team?
Team running enrichment inside AI tools or API: MoltSets. Flat-rate on emails and company data means lookup volume doesn't change the bill.
Enterprise RevOps with budget and procurement process: ZoomInfo. The broadest platform, quoted annually at a 5-figure average contract value.
Teams looking for HubSpot enrichment: Breeze Intelligence (formerly Clearbit). Native enrichment inside Hubspot.
Outbound team that wants data and sequencing in one tool: Apollo. Database, sequencer, and dialer on one bill, provided you don't need API access below a Custom plan.
Team that only needs work emails: Hunter. 1 credit to find, 0.5 to verify, from $49/mo, and nothing else to buy.
Solo rep prospecting by hand on LinkedIn: Lusha. Reveals in the browser at 1 credit per email, though phones cost five.
Engineering team building a data pipeline: People Data Labs. Raw person and company datasets from $98/mo, billed per successful match.
Is MoltSets a good data enrichment API?
MoltSets is a good enrichment API if your workflow runs through APIs, MCP, or AI tools. Emails carry a risk score, mobiles are carrier-verified in real time, pricing is flat from $27/mo, and there is no per-seat cost. It's a poor fit if your team needs a UI to build lists in.