Inbox Monster vs smtp4dev
| Inbox Monster | smtp4dev | |
|---|---|---|
| Free plan | No | No |
| Free trial | No | No |
| Paid from | $312.50/mo | — |
| Open source | No | No |
| Platforms | Web | Web, Windows, macOS, Linux |
| Free plan | No | Yes |
| Email clients | 120 clients | — |
| Device coverage | both | both |
| Spam checks | Yes | — |
| Accessibility checks | Yes | — |
| Link checks | Yes | — |
| Inbox testing | Yes | — |
| API access | Yes | Yes |
Both are listed in Best Email Testing Software. On Samsung Mobile US Press, Inbox Monster scores higher on our published basis.