Kerna vs Spike
Kerna
kerna.io
Spike
spikenow.comSide by side
| Figure | Kerna | Spike |
|---|---|---|
| Price from | €12/mo | $4/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| iOS | — | Yes |
| Android | — | Yes |
| Plans published | 5 | 12 |
| Spec score · AI Email Assistants | 8.3 (#11) | 8.3 (#12) |
| Integrations | Kerna integrates with Gmail, Outlook, Calendar, Contacts and Sheets, and the pricing page lists shared mailboxes for Outlook. | Spike supports Google Drive, Dropbox, and OneDrive for cloud attachments, and its calendar feature names Google Calendar, Outlook, and Apple Calendar. |
| Privacy | Kerna says email content is processed in memory and discarded after the request, with personal data redacted before content reaches the inference provider. | Spike says it is ad-free and does not rent, sell, distribute, or monetize user data, while non-personal data may be used to improve its service. |
| Product | Kerna is an AI email assistant that works inside Gmail and Outlook. | Spike describes itself as an AI-powered inbox that brings email, calls, notes, tasks, and to-dos into one hub and turns email threads into chat-like conversations. |
| Security | The trust page reports TLS 1.2 or higher in transit and AES-256 encryption at rest in Firestore. | Spike says message data is encrypted with AES-256 using a per-message private key and that it has periodic external security audits. |
Plans
Kerna
- StarterFree
- Standard€12 a month
- Pro€22 a month
- Business€69 a month
- Enterprise€499 a month
Spike
- StarterFree
- Team$4 a month
- Business$8 a month
- FreeFree
- Pro$6 a month
- Ultimate$12 a month
- Email App FreeFree
- Teamspace StarterFree
- Teamspace Team$4 a month
- Email App Pro$6 a month
In their own words
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.
Spike
Spike combines email, calls, notes, tasks, and to-dos in a single hub, and presents email threads as chat-like conversations. It has a unified inbox, scheduled sending, and calendar tools, and runs on Android, iOS, macOS, web, and Windows. Spike AI can draft messages and replies, summarize conversations, and provide an assistant; free tiers list 10 queries for several AI features. Teamspace adds channels, shared inboxes, groups, collaborative documents and tasks, and audio and video meetings. Spike works with existing accounts such as Gmail, Office 365 or Outlook, Exchange, iCloud, Yahoo, and other IMAP accounts. Cloud attachments can use Google Drive, Dropbox, or OneDrive, and calendars can connect with Google Calendar, Outlook, and Apple Calendar. Spike says it encrypts messages with AES-256 using a per-message private key, and undergoes periodic external security audits. The Email App Free plan includes one address, 60 days of search history, 1 GB storage, and 30 MB file uploads. Email App Pro is $6 a month billed annually; Ultimate is $12 a month billed annually.