Inbox Zero vs Kerna
Inbox Zero
inbox-zero.aiKerna
kerna.ioSide by side
| Figure | Inbox Zero | Kerna |
|---|---|---|
| Price from | $20/mo | €12/mo |
| Free plan | — | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| iOS | Yes | — |
| Android | Yes | — |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 4 | 5 |
| Spec score · AI Email Assistants | 8.4 (#8) | 8.3 (#11) |
| Headquarters | Newark, Delaware, United States | Katowice, Poland |
| Security | The hosted product is SOC 2 compliant, and the Trust Center identifies SOC 2 Type 2 compliance. | The trust page reports TLS 1.2 or higher in transit and AES-256 encryption at rest in Firestore. |
Plans
Inbox Zero
- Starter$20 a month
- Plus$35 a month
- Professional$50 a month
- EnterprisePriced on request
Kerna
- StarterFree
- Standard€12 a month
- Pro€22 a month
- Business€69 a month
- Enterprise€499 a month
In their own words
Inbox Zero
Inbox Zero has no write-up on Specifiction yet; its figures are above.
Kerna
Kerna is an AI email assistant for Gmail and Outlook on macOS, Windows, and the web. At a user’s request, it sorts open messages into categories such as Urgent, Respond, Invoice, Waiting, and Notification; users can also set custom categories and industry taxonomies. It drafts replies based on the full thread, with controls for intent and tone, and makes structured thread summaries for conversations of up to 50 messages. It can summarize attachments, extract selected fields into exportable tables, and translate inbound messages and outbound replies in 45 languages. Integrations include Calendar, Contacts, and Sheets as well as Gmail and Outlook. Kerna says it acts only when a user initiates a request, processes content in memory, discards it afterward, and redacts personal data before it reaches the inference provider. Its trust information reports TLS 1.2 or higher in transit and AES-256 encryption at rest. Kerna has a free plan; paid plans start at €12/mo. Outlook requires a Microsoft-hosted mailbox; POP or IMAP and on-premises Exchange are unsupported.