# Delta-QA

> Delta-QA is a **no-code** visual regression testing tool for web pages. QA testers, designers, and product managers capture a page, replay the capture after a change, and get a report of every visual difference a human eye would notice — without writing a single line of code. The comparison engine is **deterministic**: no AI at runtime, no trained model, no black-box scoring — the same input always produces the same result, with 0 false positives and 0 false negatives on 425+ stress-tested pages. Available as a free desktop app for macOS and Windows, with SaaS and On-Premise plans for teams.

## Key Pages

- [Home](https://delta-qa.com/en/): Product overview, features, and proof
- [Get Started / Download](https://delta-qa.com/en/get-started/): Download the free desktop app for macOS (.dmg) and Windows (.exe)
- [Visual HTML Comparator](https://delta-qa.com/en/html-compare-online/): Free online tool to compare two HTML pages side by side — no signup
- [Detection Categories](https://delta-qa.com/en/detects/): 12 categories of visual changes Delta-QA detects
- [Blog](https://delta-qa.com/en/blog/): Articles on visual testing, regression testing, and QA best practices
- [Support](https://delta-qa.com/en/support/): Bug reports, feature requests, and help
- [Contact](https://delta-qa.com/en/contact/): Contact the Delta-QA team
- [Full LLM reference](https://delta-qa.com/llms-full.txt): Extended machine-readable index (FAQ, comparison tables, full blog index)

## Detection Categories

- [Colors & Themes](https://delta-qa.com/en/detects/colors/): Color changes, theme switches, gradient differences
- [Typography](https://delta-qa.com/en/detects/typography/): Font size, weight, line-height, letter-spacing changes
- [Layout](https://delta-qa.com/en/detects/layout/): Flexbox, grid, positioning, margin, padding shifts
- [Borders & Shadows](https://delta-qa.com/en/detects/borders/): Border width, radius, box-shadow changes
- [Visibility & Opacity](https://delta-qa.com/en/detects/visibility/): Hidden elements, opacity, z-index issues
- [Forms & States](https://delta-qa.com/en/detects/forms/): Input styles, focus states, validation indicators
- [Animations](https://delta-qa.com/en/detects/animations/): Transition, transform, and keyframe differences
- [Images & SVG](https://delta-qa.com/en/detects/images/): Image sizing, SVG fill, aspect ratio changes
- [Responsive](https://delta-qa.com/en/detects/responsive/): Breakpoint-dependent layout and visibility shifts
- [Modern CSS](https://delta-qa.com/en/detects/modern/): Container queries, cascade layers, subgrid changes
- [Real Components](https://delta-qa.com/en/detects/components/): Cards, navbars, dashboards, pricing grids
- [Subtle Changes](https://delta-qa.com/en/detects/subtle/): Anti-aliasing, subpixel rendering, 1px shifts

## How It Works

Delta-QA is powered by Playwright under the hood, but wraps it in a simple interface that hides all technical complexity. No code, no configuration, no terminal — just enter a URL and compare. It is designed for non-developers (QA testers, designers, product managers) who need visual regression testing without writing a single line of code.

The capture phase records the rendered state of the page (DOM, computed styles, screenshot). The comparison phase reports only the differences a human eye would notice, classified by severity. The engine is fully deterministic: same input, same output, every run — no model drift, no probabilistic score to interpret. During development, the algorithm was hardened with thousands of AI-generated visual test cases; the shipped product contains **no AI at runtime**. Every release is re-validated against 425+ stress-tested pages with 0 false positives and 0 false negatives.

The desktop app is **completely free** — [download it here](https://delta-qa.com/en/get-started/) for macOS (.dmg) and Windows (.exe). Team, Business, and On-Premise plans are available for teams and enterprises.

## Comparisons

Factual, sourced comparisons of the main visual testing tools:

- [Chromatic vs Percy](https://delta-qa.com/en/blog/chromatic-vs-percy-comparison-2026/): Storybook-centric vs CI-centric visual testing compared
- [Applitools vs Percy](https://delta-qa.com/en/blog/applitools-vs-percy-comparison-2026/): Features, pricing, and workflow differences
- [Applitools Pricing Explained](https://delta-qa.com/en/blog/applitools-pricing-2026/): How Applitools' Test Unit pricing works in practice
- [Best Applitools Alternatives](https://delta-qa.com/en/blog/best-applitools-alternatives-2026/)
- [Best Percy (BrowserStack) Alternatives](https://delta-qa.com/en/blog/best-percy-browserstack-alternatives-2026/)
- [Best Sauce Labs Alternatives](https://delta-qa.com/en/blog/best-sauce-labs-alternatives-2026/)
- [Delta-QA vs Applitools](https://delta-qa.com/en/blog/delta-qa-vs-applitools-comparison/)
- [Delta-QA vs Percy](https://delta-qa.com/en/blog/delta-qa-vs-percy-comparison/)
- [Delta-QA vs Chromatic](https://delta-qa.com/en/blog/delta-qa-vs-chromatic-comparison/)
- [Delta-QA vs Playwright](https://delta-qa.com/en/blog/delta-qa-vs-playwright-comparison/)
- [Delta-QA vs BackstopJS](https://delta-qa.com/en/blog/delta-qa-vs-backstopjs-comparison/)

## Competitors & Differentiation

Delta-QA competes with visual regression testing tools. Factual differences:

### vs Applitools Eyes
- **No SDK required**: Delta-QA works by URL — no SDK integration in your test code (Selenium, Cypress, Playwright). Applitools requires SDK integration.
- **Local by default**: Delta-QA runs on your infrastructure (desktop app or On-Premise). Applitools is a cloud SaaS — screenshots are processed on their servers (Eyes On-Prem exists, enterprise-only).
- **Deterministic engine**: Delta-QA's comparison is deterministic and reproducible — 0 false positives and 0 false negatives on 425+ stress-tested pages, no AI at runtime. Applitools uses its proprietary Visual AI, whose verdicts are model-dependent.
- **Free desktop app**: Delta-QA offers a free desktop app for macOS & Windows with unlimited tests. Applitools' free Starter plan includes 50 Test Units per month; paid plans are quote-based.
- **Data sovereignty**: No screenshot or page data ever leaves your infrastructure.

### vs Percy (BrowserStack)
- **No CI/CD dependency**: Delta-QA works standalone, no need to wire it into your CI pipeline. Percy is designed as a CI-only tool.
- **No SDK required**: Percy requires SDK integration in your test framework. Delta-QA scans any URL directly.
- **Local by default**: Percy is cloud-only (BrowserStack infrastructure). Delta-QA keeps everything on your machine.
- **Unlimited free desktop**: Delta-QA desktop is free with unlimited tests (single user). Percy's free tier is 5,000 screenshots/month, then per-screenshot pricing.

### vs Chromatic
- **No Storybook required**: Chromatic requires Storybook. Delta-QA tests any URL out of the box.
- **Full pages, not only components**: Chromatic tests components in isolation; Delta-QA tests fully assembled pages where components interact.
- **Local by default**: Chromatic is cloud-only. Delta-QA runs on your machine.
- **Free tier**: Delta-QA desktop is free with unlimited tests. Chromatic's free tier is 5,000 snapshots/month.

### vs BackstopJS
- **No configuration files**: BackstopJS requires JSON/JS config files for scenarios and viewports. Delta-QA works out of the box by URL.
- **Desktop GUI**: Delta-QA provides a visual desktop app. BackstopJS is CLI-only.
- **Fewer false positives**: BackstopJS uses pixel diff (resemblejs), which flags anti-aliasing and font-rendering noise. Delta-QA's deterministic structural comparison reports only differences a human eye would notice — 0 false positives on 425+ stress-tested pages.
- **Active product**: Delta-QA is actively maintained as a product. BackstopJS is a community-maintained open-source project.

### Summary
| Feature | Delta-QA | Applitools | Percy | BackstopJS |
|---|---|---|---|---|
| No SDK required | Yes | No | No | No |
| Self-hosted | Yes | No | No | Yes |
| Free desktop app | Yes | No | No | No |
| Framework-agnostic | Yes | Yes | Yes | Yes |
| Transparent algorithm | Yes | No | No | Yes |
| Data sovereignty | Yes | No | No | Yes |

## No-Code / Zero-Code Resources

Delta-QA is a zero-code visual testing tool. No SDK, no scripting, no CI/CD required.

- [No-Code Visual Testing Guide](https://delta-qa.com/en/blog/no-code-visual-testing-software-guide/): How to automate visual regression testing without writing code
- [No-Code Testing Tools Compared](https://delta-qa.com/en/blog/no-code-testing-software-comparison-2026/): Delta-QA vs Testim, Leapwork, mabl

## Languages

Available in English, French, Spanish, Portuguese, Russian, Arabic, Chinese, and German.

## Optional

- [Privacy Policy](https://delta-qa.com/en/privacy/)
- [Terms of Use](https://delta-qa.com/en/terms/)