**Last updated**: 24 June 2025 | [**Change log**](/products/checkout/web/changelog/)

# Additional information

## Browser support

### Browser Dependencies

- ES5
- PostMessage
- DOM
- classList
- appendChild


## Cross-platform support (~96% global traffic)

### Devices + Browsers + OS

Global Desktop Browser support list:

| Browser | Version | Market Share | Unsupported |
|  --- | --- | --- | --- |
| IE | 11+ | 5.41% | 0.89% < v11 |
| Edge | 15+ | 4.01% | 0.24% < v15 |
| Chrome | 29+ | 63.9% | 0.21% < v29 |
| Firefox | 27+ | 10.25% | 0.11% < v27 |
| Safari | 7+ | 5.14% | 0.22% < v7 |
| Opera | 16+ | 2.13% | 0.22% < v16 |


#### Mobile browser support list:

| Browser | Version | Market Share |
|  --- | --- | --- |
| iOS Safari | 6+ | 20.11% |
| Android Chrome | 70+ | 57.22% |
| Android Firefox | 63+ | <1% |
| UC Browser | 11.8+ | 8.02% |
| Android Opera | 12.1+ | 4.05% |


### Additional support

- Pixel density
- Browser card managers
- Zoom levels
- Touch navigation
- Multiple viewports


## Dev Dependencies

- TypeScript - superset of JavaScript (ES5 + ES Next + Types)
- TSLint - TypeScript linting tool
- Karma - Test Runner tool
- Mocha - Test framework
- Chai - Assertion library
- Webpack - Module bundler
- Istanbul - Code coverage tool
- Selenium - UI testing framework
- Express - Node web app framework


br
**Next steps**

[Create `sessionState`](/products/checkout/web/v1/create-sessionstate-web)