# Email on Acid

**Canonical:** https://apis.io/providers/email-on-acid/  
**Website:** https://www.emailonacid.com  
**APIs profiled:** 4

Email on Acid (now branded as Mailgun Inspect) is an email testing and pre-deployment quality assurance platform with a REST API for rendering email previews across 100+ email clients and devices, checking accessibility compliance (WCAG 2.2), validating HTML/CSS compatibility, running spam filter analysis, and automating pre-send email testing workflows via HTTP Basic Authentication.

## Kin Score — 48.5 / 100 (developing)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 48.5).

| Facet | Score |
|---|---|
| Discoverability | 74.1 |
| Contract Quality | 67.1 |
| Governance | 9.8 |
| Contract Governance | 9.8 |
| Operational Transparency | 52.6 |
| Developer Ergonomics | 23.8 |
| Commercial Clarity | 57.9 |
| Access Clarity | 57.9 |

## Agent readiness — 32.1 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | partial |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## Access

Paid · Self-serve signup — onboarding: self-serve, pricing: paid, trial: no (confidence: high).

## APIs (4)

- **Email on Acid Authentication API** — Verify API credentials
- **Email on Acid Email Clients API** — Manage email client lists and defaults for testing
- **Email on Acid Email Testing API** — Create and manage email rendering tests
- **Email on Acid Spam Testing API** — Standalone spam filter analysis and seed list management

## Agentic access (1)

- **Email On Acid Agentic Access** — 23 operations · 6 acting

## Security (3)

- **Email On Acid Authentication** — http · 1 scheme
- **Email On Acid Domain Security** — TLSv1.3 · HSTS · DMARC
- **Email On Acid Trust Center** — SOC 2, ISO 27001, GDPR

## Plans (1)

- **Email On Acid Plans Pricing**

## Tags

Email Testing, Email Previews, Email Clients, Spam Testing, Accessibility, HTML Validation, Email Quality Assurance, Pre-Deployment Testing

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/email-on-acid/). Scores are computed from the provider's own public artifacts under a published rubric.