# Clay vs ZeroBounce

> ZeroBounce scores 62.4 (B) to Clay's 56.4 (C) for lead enrichment. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/clay-vs-zerobounce
- Markdown: https://www.anchorterminal.com/compare/clay-vs-zerobounce.md (~4,400 tokens)
- Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- DNS: dig +short TXT <slug>.grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.<category>. and <a>.vs.<b>. under the zone, and the same under grade.letme.dev)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-11-07

ZeroBounce scores 62.4 (B) on agent readiness against Clay's 56.4 (C), and leads in 5 of 7 scored categories. Clay leads on schema & documentation and maintenance & community. Both do lead enrichment.

- Clay: grade C, 56.4/100, rank #831 of 1510. Markdown https://www.anchorterminal.com/tools/clay.md · JSON https://www.anchorterminal.com/api/v1/tools/clay.json
- ZeroBounce: grade B, 62.4/100, rank #561 of 1510. Markdown https://www.anchorterminal.com/tools/zerobounce.md · JSON https://www.anchorterminal.com/api/v1/tools/zerobounce.json
- Best lead, contact and company data APIs for AI agents: https://www.anchorterminal.com/best/lead-data/index.md
- All 231 leads comparisons: https://www.anchorterminal.com/compare/lead-data/index.md

## Which one, for what

### Clay (C)

Good for: Agents building prospect lists and enriching contacts or accounts through many providers at once.

Ahead on:
- Schema & documentation, 84 against 54
- Maintenance & community, 75 against 70

Watch for: API keys carry no scopes and act with the user's workspace access

### ZeroBounce (B)

Good for: Email verification before outreach, the verification-first listing in lead-data.

Ahead on:
- Reliability, 75 against 40
- Security & auth, 65 against 48
- Payments & pricing, 35 against 30

Also in its favour:
- Runs on your own machine

Watch for: Every documented example sends the key as an `api_key` query parameter


## Why the edge

### Reliability: ZeroBounce +35

- Clay (40): Graded with the hosted lines on the Public API. status.clay.com is linked from every page footer but answered with a Cloudflare bot check on 14 October, and on 4 November its robots.txt answered the same check, so the host is treated as blocked and its components stay unconfirmed (10 of 20, per the 14 October check, not re-read on 4 November). No readable history (5). A per-workspace request limit with no number, and published search-result caps per plan (8 of 15). 429 with Retry-After and X-RateLimit headers, backoff with jitter, and retries of 5xx only when a request is safe to retry, re-read on 4 November. No idempotency keys (12 of 15). The terms of 1 November 2026 replaced the May 2024 version and no longer set the 99.0 per cent monthly uptime target with fee credits, and no other SLA was found (0). The API is v0, and Workflows and run search are labelled alpha or beta (5 of 10). 10 + 5 + 8 + 12 + 0 + 5 = 40.
- ZeroBounce (75): Hosted lines. Statuspage at status.zerobounce.net with API, API-US, API-EU, Bulk API, website and Cloudflare components (20). The incident feed for 8 August to 6 November shows a 6-minute members platform disruption on 9 September, about 3 minutes of reduced EU API availability on 1 October, and a file upload issue on 26 October resolved within 6 minutes, all minor (20). Limits published per endpoint group with numbers and block lengths (15). 429 is documented with advice to throttle, but no Retry-After, and a block can last an hour or a day (10 of 15). No SLA found (0). Generally available (10). 20+20+15+10+0+10 = 75.

### Schema & documentation: Clay +30

- Clay (84): A public OpenAPI 3 spec, per the 14 October check (25). llms.txt and Markdown copies of every page, re-read on 4 November, with 18 API reference pages now that Audiences privacy deletion and its status call were added in the week of 26 October (10). Pages say when to use each primitive, and deprecated filters-mode endpoints name their replacement (16 of 20). Typed request bodies, with a query grammar fetched from a reference endpoint rather than enums (12 of 15). curl examples on every guide, but error bodies carry only a message, and the errors page says they don't include stable codes (9 of 15). v0 in the path and a weekly product changelog that names CLI, MCP and API changes, without an API-specific log (12 of 15). 25 + 10 + 16 + 12 + 9 + 12 = 84.
- ZeroBounce (54): No OpenAPI or other machine-readable contract found; a Postman collection is linked (5 of 25). llms.txt lists marketing pages, and the docs have no Markdown twins (5 of 10). Endpoint pages explain timing, credits and when to use batch or file APIs (14 of 20). Parameter tables and listed status and sub-status values, including the ai_agent_mailbox sub-status added in July 2026 (10 of 15). Examples per endpoint, a sandbox and an error-code page (12 of 15). v2 paths, an API migration page and dated maintenance notices on the status page, with no API changelog (8 of 15). 5+5+14+10+12+8 = 54.

### Security & auth: ZeroBounce +17

- Clay (48): A personal API key tied to the user's workspace access, with no scopes documented. The CLI uses OAuth per workspace (15 of 30). Functions need API or MCP access switched on one by one, workspace roles apply, and the changelog adds IP access restrictions (week of 21 September) and MCP client allowlisting (week of 26 October). CLI 1.14.0 (3 November) can hold commands that delete, send or run at scale for the user's approval, but the Claude Code plugin's hook still auto-approves most clay CLI commands, including ones that spend credits (8 of 20). Claygent web research returns untrusted text, and no injection guidance was found (3 of 15). Credit balances and a workflow-run query, with no per-call audit log found (6 of 15). security.txt valid to 31 July 2027 naming security@clay.com and trust.clay.com, re-read on 4 November, and SOC 2 Type II, ISO 27001 and ISO 42001 listed on the pricing page. No bug bounty found (16 of 20). 15 + 8 + 3 + 6 + 16 = 48.
- ZeroBounce (65): Several named keys besides a Master key, regeneration, deactivation and IP whitelists (25), less 10 because the documented calls carry the key in the `api_key` query string (15 of 30). Validation only reads, though file and list endpoints can delete uploads (12 of 20). Results are structured status codes with little free text (10 of 15). API usage and dashboard statistics endpoints (10 of 15). SOC 2 Type 2, ISO/IEC 27001:2022, continuous testing with Intigriti and penetration testing with BitSentinel; no public disclosure policy found (18 of 20). 15+12+10+10+18 = 65.

### Payments & pricing: ZeroBounce +5

- Clay (30): No x402, MPP or L402 (0). Data credits from $0.05 and plan prices public, though on 4 November the plan cards still say $167 and $446 a month for Launch and Growth while the FAQ says $185 and $495 (15 of 20). A free plan with 100 data credits and 500 actions a month, and a page footer saying no credit card is required, while the FAQ lists Clay API access under Enterprise (15 of 20). A person signs up in a browser, and CLI sign-in opens a browser or a device code (0). 0 + 15 + 15 + 0 = 30.
- ZeroBounce (35): No x402, MPP or L402 (0). Per-credit prices public, from $39 for 2,000 validations (20). Freemium of 100 validations a month for business or premium domains; a card requirement isn't stated, and free webmail addresses don't qualify (15 of 20). A person signs up in a browser (0). 0+20+15+0 = 35.

### Maintenance & community: Clay +5

- Clay (75): clay plugin 2.35.0 on 4 November 2026, requiring CLI 1.14.0, whose tag sits on the 3 November release commit (30). 36 plugin releases from 7 August to 4 November, the last three (15 October, 3 and 4 November) changing skill content, plus weekly dated product roundups to the week of 26 October (20). Weekly dated product roundups and a support address, with the plugin's issue handling not visible (12 of 15). No official SDKs, the CLI is current (8 of 15). CLI binaries ship from GitHub releases, and the repository has no licence file (5 of 10). 30 + 20 + 12 + 8 + 5 = 75.
- ZeroBounce (70): Closed service. The JavaScript SDK 3.0.0 was published on 25 October 2026 (30). No API changelog; the dated changes found in 90 days are that release and status-page notices, fewer than three releases (10 of 20). Support by email and 24/7 chat per the docs, a public status page; replies not tested (10 of 15). Official SDKs in many languages and an MCP server (15). Package health not checked (5 of 10). 30+10+10+15+5 = 70.

## Score by category

| Category | Weight | Clay | ZeroBounce | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 40 | 75 | ZeroBounce +35 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 84 | 54 | Clay +30 |
| Agent ergonomics | 13% (16.2 this run) | 66 | 69 | ZeroBounce +3 |
| Security & auth | 14% (17.5 this run) | 48 | 65 | ZeroBounce +17 |
| Payments & pricing | 10% (12.5 this run) | 30 | 35 | ZeroBounce +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 75 | 70 | Clay +5 |
| Transparency & trust | 7% (8.8 this run) | 61 | 63 | ZeroBounce +2 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **56.4 · C** | **62.4 · B** | |

## Facts side by side

| Fact | Clay | ZeroBounce |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Clay Labs Inc. | Hertza L.L.C. (ZeroBounce) |
| Hosted endpoint | `https://api.clay.com/public/v0` | `https://api.zerobounce.net/v2` |
| Transports | HTTP | HTTP, stdio |
| Auth | OAuth or key | API key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | Proprietary service under the Clay Terms of Service. The agent plugin repository carries no licence file | Proprietary service under ZeroBounce's terms of use; SDKs and the MCP server are open source |
| Tools exposed | none | 0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-11-04 | 2026-10-25 |
| Terms last updated | not read yet | 2026-05-05 |
| Privacy policy last updated | 2020-09-11 | 2026-06-30 |
| Customer content may train models | not read yet | not found in the text |
| Terms restrict automated access | not read yet | not found in the text |
| Terms restrict benchmarking | not read yet | not found in the text |
| Terms or service can change without notice | not read yet | yes |
| Arbitration or class-action waiver | not read yet | yes |

## How the scores have moved

### Clay

- -1.3 on 4 November 2026: terms

### ZeroBounce

No score change since it was listed.

## Verdicts

**Clay.** A documented Public API with an OpenAPI spec, llms.txt and plan-capped search, plus a JSON-first CLI and plugin released 36 times since 7 August, give agents Clay's people search and multi-provider enrichment. Keys have no scopes, the Claude Code plugin auto-approves most CLI calls, the new terms set no uptime target, and the privacy policy dates from 2020.

**ZeroBounce.** ZeroBounce's v2 API verifies emails with detailed status and sub-status codes, publishes per-endpoint limits, a Statuspage with short incidents only in the last 90 days, SOC 2 Type 2 and ISO 27001, and $0.0195 per email at the smallest pack. The documented key travels in the query string, and there is no OpenAPI contract.

## Before you call either

### Clay

1. Fetch GET /search/query-mode/reference before writing a search query
2. Poll routine results until a terminal 200, since 202 means still running
3. Expect HTTP 402 when a plan's search cap is hit, and tell the user the reset date
4. Check GET /credits/balance before large batch runs
5. When a CLI command answers approval_required, tell the user what it would do and let them approve or deny it
6. Ask the user before enabling the plugin's auto-approve hook in a shared workspace

### ZeroBounce

1. Use the regional host (api-us or api-eu) that matches the data, and test with the sandbox addresses, which spend no credits
2. Set `timeout` (3 to 60 seconds); slow mail servers return unknown, which is free to retry later
3. Stay under 80,000 validations per 10 seconds and avoid repeated bad requests, which block the key for an hour
4. Use the bulk file API for large lists instead of looping on /v2/validate
5. Keep the key out of logs; the API takes it only as `api_key` in the URL

## Questions

### Which is better for AI agents, Clay or ZeroBounce?

ZeroBounce scores 62.4 (B) on agent readiness against Clay's 56.4 (C), and leads in 5 of 7 scored categories. Clay leads on schema & documentation and maintenance & community.

### Do Clay and ZeroBounce need an API key?

Clay takes an API key or an OAuth sign-in. ZeroBounce needs an API key.

### Can an agent call Clay and ZeroBounce without installing anything?

Yes. Clay has a hosted endpoint at https://api.clay.com/public/v0 and ZeroBounce at https://api.zerobounce.net/v2.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/clay-vs-zerobounce.json, and with the fewest tokens: https://www.anchorterminal.com/compare/clay-vs-zerobounce.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "clay", "b": "zerobounce"}`. From a terminal: `anchor compare clay zerobounce`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/clay.json and https://www.anchorterminal.com/api/v1/tools/zerobounce.json

## Other comparisons with Clay or ZeroBounce

- [Apollo API + MCP vs Clay](https://www.anchorterminal.com/compare/apollo-vs-clay.md)
- [Clay vs Coresignal API + MCP](https://www.anchorterminal.com/compare/clay-vs-coresignal.md)
- [Clay vs Crustdata API + MCP](https://www.anchorterminal.com/compare/clay-vs-crustdata.md)
- [Clay vs Databar](https://www.anchorterminal.com/compare/clay-vs-databar.md)
- [Clay vs Dievio](https://www.anchorterminal.com/compare/clay-vs-dievio.md)
- [Clay vs Enrich Layer API + MCP](https://www.anchorterminal.com/compare/clay-vs-enrich-layer.md)
- [Clay vs Explorium AgentSource](https://www.anchorterminal.com/compare/clay-vs-explorium-agentsource.md)
- [Clay vs FullEnrich API + MCP](https://www.anchorterminal.com/compare/clay-vs-fullenrich.md)
- [Clay vs Fuse MCP](https://www.anchorterminal.com/compare/clay-vs-fuse-mcp.md)
- [Clay vs Gojiberry](https://www.anchorterminal.com/compare/clay-vs-gojiberry.md)
- [Clay vs Hunter API + MCP](https://www.anchorterminal.com/compare/clay-vs-hunter.md)
- [Clay vs LeadMagic API + MCP](https://www.anchorterminal.com/compare/clay-vs-leadmagic.md)
- [Clay vs Lusha API + MCP](https://www.anchorterminal.com/compare/clay-vs-lusha.md)
- [Clay vs People Data Labs](https://www.anchorterminal.com/compare/clay-vs-people-data-labs.md)
- [Clay vs Prospeo API + MCP](https://www.anchorterminal.com/compare/clay-vs-prospeo.md)
- [Clay vs RocketReach API](https://www.anchorterminal.com/compare/clay-vs-rocketreach.md)
- [Clay vs ZoomInfo API + MCP](https://www.anchorterminal.com/compare/clay-vs-zoominfo.md)
- [Apollo API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/apollo-vs-zerobounce.md)
- [Clay vs Clearbit](https://www.anchorterminal.com/compare/clay-vs-clearbit.md)
- [Clay vs Dropcontact API + MCP](https://www.anchorterminal.com/compare/clay-vs-dropcontact.md)
- [Clay vs FullContact](https://www.anchorterminal.com/compare/clay-vs-fullcontact.md)
- [Clearbit vs ZeroBounce](https://www.anchorterminal.com/compare/clearbit-vs-zerobounce.md)
- [Coresignal API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/coresignal-vs-zerobounce.md)
- [Crustdata API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/crustdata-vs-zerobounce.md)
- [Databar vs ZeroBounce](https://www.anchorterminal.com/compare/databar-vs-zerobounce.md)
- [Dievio vs ZeroBounce](https://www.anchorterminal.com/compare/dievio-vs-zerobounce.md)
- [Dropcontact API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/dropcontact-vs-zerobounce.md)
- [Enrich Layer API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/enrich-layer-vs-zerobounce.md)
- [Explorium AgentSource vs ZeroBounce](https://www.anchorterminal.com/compare/explorium-agentsource-vs-zerobounce.md)
- [FullContact vs ZeroBounce](https://www.anchorterminal.com/compare/fullcontact-vs-zerobounce.md)
- [FullEnrich API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/fullenrich-vs-zerobounce.md)
- [Gojiberry vs ZeroBounce](https://www.anchorterminal.com/compare/gojiberry-vs-zerobounce.md)
- [Lusha API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/lusha-vs-zerobounce.md)
- [People Data Labs vs ZeroBounce](https://www.anchorterminal.com/compare/people-data-labs-vs-zerobounce.md)
- [Prospeo API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/prospeo-vs-zerobounce.md)
- [ZeroBounce vs ZoomInfo API + MCP](https://www.anchorterminal.com/compare/zerobounce-vs-zoominfo.md)
- [Hunter API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/hunter-vs-zerobounce.md)
- [Fuse MCP vs ZeroBounce](https://www.anchorterminal.com/compare/fuse-mcp-vs-zerobounce.md)
- [LeadMagic API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/leadmagic-vs-zerobounce.md)
- [RocketReach API vs ZeroBounce](https://www.anchorterminal.com/compare/rocketreach-vs-zerobounce.md)

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Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp