Overview
Summary
The useful answer before the supporting detail.
Happo is a visual UI testing platform that screenshots components and pages across browsers to catch visual regressions before they ship S1. It is used by front-end engineers and teams who want to modernize their testing workflow, especially those working with Storybook, browser rendering, Cypress, or native apps S1. Its practical value is catching unintended visual changes early, including accessibility violations, and integrating with CI/CD to prevent regressions S56.
Product identity and positioning
Name, category, positioning, audience, and first-party claims.
- Identity: Happo, a visual UI testing platform S1.
- Core purpose: Catches visual regressions and accessibility issues in UI changes S56.
- Intended users: Front-end engineers and teams shipping UI, including those using AI agents S1 S56.
- Product scope: A hosted web service with API, MCP server, and integrations; not a full testing suite S14 S23.
- Positioning: Self-bootstrapped, no venture capital, built by engineers with experience at Airbnb S1.
- Claimed distinction: Supports more browsers, cheaper than competitors, and includes accessibility testing S1 S56.
Use cases and audiences
Who the product serves and the jobs it is designed to handle.
| Audience | Practical use case |
|---|---|
| Front-end teams using Storybook | Screenshot stories to catch visual regressions in components S56. |
| Teams using browser rendering or Cypress | Integrate visual testing into existing test suites S1. |
| Mobile app teams (iOS/Android) | Snapshot screens and components in native test setups via API S56. |
| Teams coding with AI agents | Use MCP server to let agents inspect and resolve visual diffs S56 S23. |
Features
Features and capabilities
Core functions and evidence-backed product capabilities.
| Capability | What it does |
|---|---|
| Cross-browser screenshot testing | Captures screenshots in Chrome, Firefox, Safari, Edge, and mobile Safari to compare visual output S56. |
| Visual regression detection | Compares screenshots between commits and highlights diffs, filtering out those under a threshold S56. |
| Accessibility testing | Runs accessibility checks, blocks approval on new violations, and grades violations by impact over time S56. |
| Animation testing | Captures and compares animations frame-by-frame, supporting CSS, SVG, Lottie, canvas, and video S56. |
| CI/CD integration | Integrates with CI/CD to catch regressions early and post status on pull requests S56. |
| API for custom integrations | Public REST-like API for uploading snapshots, creating reports, and orchestrating comparisons S14. |
| MCP server for AI agents | Lets AI assistants inspect and resolve visual-regression comparisons via MCP S23. |
Integrations and ecosystem
Connected products, exports, APIs, and workflow compatibility.
| Integration or interface | Type | What it enables |
|---|---|---|
| Storybook | Integration | Screenshots stories directly from Storybook S56. |
| browser rendering | Integration | Screenshots pages from browser rendering tests S56. |
| Cypress | Integration | Screenshots pages from Cypress tests S56. |
| Native iOS/Android apps | API | Uploads screenshots from native test setups via the Happo API S56. |
| Public REST API | API | Create or enhance custom integrations, upload snapshots, manage reports S14. |
| MCP server | AI interface | Lets AI assistants (AI model, ChatGPT, Cursor) inspect and resolve visual-regression comparisons S23. |
| GitHub and CI | Integration | Posts status on pull requests and integrates with CI/CD S56. |
Pricing
Pricing and plans
Published plans, free access, trials, credits, and pricing limitations.
| Plan or offer | Verified price and billing | Included | Limits |
|---|---|---|---|
| Free | $0 per month S171 | 5,000 snapshots per month, unlimited users, accessibility testing S171 | Pauses at the limit S171 |
| Starter | $149 per month S171 | 50,000 snapshots per month, unlimited users, accessibility testing S171 | Then $0.006 per snapshot S171 |
| Growth | $399 per month S171 | 150,000 snapshots per month, unlimited users, accessibility testing S171 | Then $0.006 per snapshot S171 |
| Scale | $749 per month S171 | 300,000 snapshots per month, unlimited users, accessibility testing S171 | Then $0.006 per snapshot S171 |
| Enterprise | Custom pricing S171 | 1 million snapshots and up, every browser, SSO, flake dashboard S171 | Custom S171 |
Trust and proof
Customers, proof, and reviews
Published proof, customer signals, and review evidence.
Independent reviews
| Platform | Page | How it was found | Note |
|---|---|---|---|
| happo.io | API Reference – Happo | Grounded web search | Happo exposes a public, REST-like, API that you can use to create or enhance custom integrations. The API resides at `https://happo.io`, and all endpoints use the `/api` namespace. OpenAPI spec for the public Happo API ... Want to use Happo from AI model, ChatGPT, Cursor, or another AI assistant? Happo also runs an MCP server with OAuth so AI agents can list comparisons, inspect diffs, and accept, reject, or report flakes for them. |
Customer proof
No named customers, testimonials, or customer case studies were found.
Independent mentions
- happo/happo.io — into your CI environment to compare the visual appearance of UI components before and after a change. ... are taken in different browsers and across different screen sizes to ensure consistent cross-browser and responsive styling of your application
- happo.io — .io Visual diffing for UI components - Version: 13.0.1 - License: MIT - Homepage: https://github.com/happo/happo.io#readme - Author: Henric Trotzig - Repository: git+https://github.com/happo/happo.io.git - Created: 2017-09-25T10:01:24.359Z - Updated:
- Happo - Visual Regression & Accessibility Testing — Happo - Visual Regression & Accessibility Testing ... # See every UI change before your users do. ... Happo catches visual regressions of every kind on every pull request, from a button that moved to a contrast that dropped to an animation that changed. In Chrome, Firefox, Safari, and Edge, on iPhone and iPad, and in your native iOS and Android apps. ... Your Storybook stories, browser rendering and Cypress tests, or your own pages: Happo screenshots them in Chrome, Firefox, Safari, and Edge, and in Sa
- About Happo / Visual UI Testing Platform — We've spent careers shipping UI at places like Airbnb, and we know how fragile even the best teams' interfaces can get. Happo is the self-bootstrapped visual and accessibility regression testing platform we started building in 2014 to fix that. We still build it, support it, and answer every email ourselves.
- Getting started / Happo docs — Happo is a visual regression testing service with support for multiple browsers and accessibility testing. It renders your UI in real browsers, takes screenshots, and compares them against a previous version so you can see exactly what changed before it ships. Set it up to run in CI and get build statuses posted directly to your pull requests. ... A run looks like this: the `happo` CLI builds your test suite and uploads it,
- Pricing – Happo — # Pay for what you test. Bring the whole team. ... Every plan comes with unlimited users, unlimited concurrent runs, and accessibility testing. You choose the browsers and how many snapshots you take, and that’s the whole bill. ... Every account starts free with 5,000 snapshots a month. No credit card needed.
- Happo.io documentation — Happo.io documentation If you are not redirected automatically, follow this link.
- [browser rendering visual regression testing – Happo](https://happo.io/browser rendering) — # Your tests passed. Did the page? browser rendering tells you the checkout button is there. Happo shows you how it looks in Chrome, Firefox, Edge, Safari, and on iPhone, and what your pull request changed. It’s one line in the tests you already have.
External links were grounded in one live web search. Search snippets are leads, not independently scraped page content; rejected links remain available in Review evidence.
Company, security, and trust
Ownership, policies, security signals, and public trust evidence.
| Signal | Finding | Source |
|---|---|---|
| Company and ownership | Founder-led support | source |
| Contact and support | If you're ready to modernize your front-end testing, we're ready to help. Contact us to learn more or get started. | source |
| Legal and privacy | POST `/api/jobs/:sha1/:sha2/cancel` | source |
| Security and compliance | Single sign-on for bigger teams, and dark mode. | source |
| Uptime and status page | Every security incident triggers a structured root-cause analysis (5 Whys) and a written postmortem. | source |
Every trust signal above is backed by a collected page or a registration record.
Documentation and product updates
Help resources, product guidance, and visible changes over time.
| Resource or update | Type | What is available | Date or freshness |
|---|---|---|---|
| API Reference – Happo | API reference | Covers authentication, MCP setup, endpoints and payloads, rate limits and errors, code examples. (source) | Not dated |
| Contact and support | Support | Public contact and support channel. (source) | Not dated |
| Happo MCP server | Documentation | Happo is a cross-browser screenshot testing and visual regression testing service. Prevent visual defects, visualize UI changes, and keep a visual log of your UI. Easy integration with tools like Storybook, browser rendering, and Cypress as well as continuous integration (CI) services like GitHub Actions, CircleCI, Travis, and Jenkins. (source) | Not dated |
| happo for npm release notes · Happo | Release notes | What changed in each release. The happo npm package: the CLI and its Storybook, Cypress, and browser rendering integrations. (source) | Not dated |
| Contact and support | Support | Public contact and support channel. (source) | Not dated |
| Happo - Visual Regression & Accessibility Testing | Roadmap | Public product roadmap. (source) | Not dated |
Not found in the collected public sources: status page, separate help center or knowledge base.
Technical
Technical and delivery signals
Delivery model, platforms, API, data ownership, reliability claims and release activity.
| Signal | Finding | Source |
|---|---|---|
| Delivery model (cloud, self-hosted, desktop, browser extension) | Cloud-hosted service with a hosted MCP server at https://happo.io/api/mcp S56. | S56 |
| Platforms and apps | Supports Chrome, Firefox, Safari, Edge, and Safari on iPhone and iPad S56. | S56 |
| API and extensibility (API, SDK, webhooks, MCP, plugins) | Public REST-like API and MCP server for AI agents S14 S23. | S14 S23 |
| Data ownership and export | Not published on the collected pages. | — |
| Performance and reliability claims | Speed of image comparison is impressive (user quote) S56. | S56 |
| Release activity | Storybook, Cypress, and browser rendering support shipped at various times S56. | S56 |
Measured infrastructure
Domain, certificate, and hosting signals, measured directly.
| Signal | Finding |
|---|---|
| First archived | 2018-12-05 — web archive |
| TLS certificate | Let's Encrypt, valid, expires 2026-12-04 |
| Security headers | HSTS, X-Content-Type-Options, X-Frame-Options |
| Headers not served | CSP, Referrer-Policy |
| Mail handled by | aspmx.l.google.com, alt1.aspmx.l.google.com |
| Nameservers | ns-84-b.gandi.net, ns-143-c.gandi.net |
Not measurable: rdap: no RDAP server published for .io. A gap here means the lookup was unavailable, not that the finding is negative.
Limits and method
Limitations and open questions
Known constraints and missing evidence from the collected pages.
The collected pages do not document any explicit limitations or gaps. Pricing details for Enterprise are custom and not published S171. No competitor names are mentioned on the site except Percy, which is named as a direct competitor S1. External review profiles were not collected, so independent ratings are not established.
Sources, method, and limitations
Evidence inventory, collection method, provider use, and constraints.
This report is based on 15 collected pages from happo.io, including the homepage, About, Pricing, API Reference, and MCP server documentation. Evidence was gathered via static and browser rendering rendering; external proof search was enabled but only one request was made, and no external review profiles were scraped. Claims are cited with source tokens S1–S171. Limitations: pricing and feature details are from the vendor's own pages and may not reflect current offerings.
- Official Websitehttps://happo.io/Verified
- Official Websitehttps://happo.io/aboutVerified
- Documentationhttps://happo.io/docs/apiVerified
- Pricing Pagehttps://happo.io/pricingVerified
- Official Websitehttps://happo.io/blog/introducing-hassle-free-support-with-happo-ios-latest-featureVerified
- Official Websitehttps://happo.io/blog/total-control-and-security-with-happo-on-premise-solutionsVerified
- Documentationhttps://happo.io/blog/the-hidden-challenges-of-screenshot-testing-for-native-apps-and-how-teamsVerified
- Documentationhttps://happo.io/docs/mcpVerified
- Official Websitehttps://happo.io/blog/new-review-experienceVerified
- Official Websitehttps://happo.io/blog/one-click-reviewsVerified
- Official Websitehttps://happo.io/release-notes/happoVerified
- Official Websitehttps://happo.io/privacyVerified
- Official Websitehttps://happo.io/securityVerified
- Official Websitehttps://happo.io/contactVerified
- Official Websitehttps://happo.io/accessibilityVerified
- Articlehttps://github.com/happo/happo.ioVerified
- Articlehttps://www.npmjs.com/package/happo.ioVerified
- Articlehttps://docs.happo.io/docs/getting-startedVerified
- Articlehttps://docs.happo.io/Verified
- Articlehttps://happo.io/playwrightVerified
- Articlehttps://happo.io/brandVerified