AtData vs ZeroBounce (2026): which should you pick?

AtData

• Developers adding email checks to sign-up or checkout through a REST API
• Senders with large lists who want scheduled re-checks of stored addresses
• Teams that want demographic or identity data alongside verification

ZeroBounce

• Marketers cleaning large lists before a campaign
• Developers checking sign-ups through an API
• Small senders who want verification, warm-up and DMARC on one bill

AtData

• No prices are published on pages we could read: the site's main pages answered with a bot check, so pricing is recorded as unverified.
• Getting an API key starts with a request to AtData's support, per the Getting Started guide; there is no self-serve signup described in the docs.
• The quality score is part of a SafeToSend subscription and is not available to credit-based users.
• Documentation is API-first, and no mailbox warm-up or DMARC monitoring is described.

ZeroBounce

• Warm-up and DMARC monitoring come only with ZeroBounce ONE, and it covers a single DMARC domain.
• Unused tests, monitors, searches and warm-up seeds on ONE do not roll over; only verification credits do.
• The FAQ says credits never expire with an active ONE subscription; otherwise expiry rules may apply depending on when they were bought.
• The free credits need a business or premium email domain at sign-up.

AtData

SafeToSend verification

A GET endpoint that checks syntax, corrects misspellings, checks the mailbox and domain, and flags spam traps and other high-risk addresses. It returns one of 30 status codes.

Quality score

A 0 to 10 score based on open signals, website visits and e-commerce activity tied to the address. The docs say it comes with a SafeToSend subscription and is not available to credit users.

List Guard monitoring

Checks a stored email list for dead and toxic addresses on a regular basis. Results can be read in the InstantData account or pulled by API as CSV.

Bulk list API

Runs files of up to 1,000,000 records through SafeToSend, email validation, demographics or identity matching.

Identity matching and demographics

Finds an alternate email or postal address from one point of contact, and returns demographic and behavioral data for a single email or postal address.

Website visitor ID and fraud APIs

The docs also cover a website visitor identification script and a separate Fraud Prevention API that uses email intelligence for risk decisions.

ZeroBounce

Email validation

Checks lists by file upload or real-time API and flags invalid, catch-all, disposable, role-based, abuse and spam-trap addresses. Unknown results and duplicates are free.

AI scoring

An AI model scores each address for quality at one extra credit, which helps decide whether to send to catch-all and other uncertain addresses.

Email Finder

Finds a person's work address from a name and company domain, at 20 credits per successful search; unknown results cost nothing.

Warm-up and placement tests

ZeroBounce ONE includes warm-up through a seed network, inbox placement tests against 20+ providers and email server tests.

Blacklist and DMARC monitoring

Monitors IPs and domains on blacklists and gathers daily DMARC reports for one domain on the ONE plan.

API, SDKs and iOS app

A validation and scoring API with SDKs in 16 languages, an MCP server, and an iOS app for checking lists from an iPhone or iPad.

AtData

Pricing could not be confirmed. See atdata.com.

ZeroBounce

• Freemium$0

  100 verification credits that refill each month, one inbox placement test, one server test and one blacklist monitor.

• Pay-As-You-Go$39

  one-time for 2,000 credits

  The minimum purchase. Per-credit rates fall with volume: about $129 for 10,000 ($0.0129 each) and $0.0032 each at 1 million.

• ZeroBounce ONE$79

  per month for 10,000 credits, billed annually ($99 monthly)

  Credits roll over, plus 250 warm-up seeds, 100 inbox tests, 100 server tests, 10 blacklist monitors, 1 DMARC domain and 15% off extra credits.

• EnterpriseCustom

  Purchases or subscriptions of more than 1 million credits, with onboarding and training.

AtData

No public discounts listed.

ZeroBounce

• Annual discount

  20% off ZeroBounce ONE billed annually

  ZeroBounce ONE costs $79 a month when paid annually in one charge, against $99 billed monthly.