Formspree vs Knock
Form backend as a service — point your HTML form at a URL and done
vs. Notifications-as-a-service: in-app feeds, email, push, SMS, chat via one API
Pricing tiers
Formspree
Free
$0. 50 submissions/mo. 1 form. Formspree branding in emails. Basic spam filtering.
Free
Basic
$10/mo. 500 submissions/mo. Unlimited forms. Custom success redirect. Honeypot anti-spam.
$10/mo
Professional
$20/mo. 1,000 submissions/mo. reCAPTCHA, webhooks, integrations, rules engine.
$20/mo
Unlimited
$40/mo. 2,500 submissions. File uploads, team members, priority support.
$40/mo
Enterprise
Custom. SSO, SAML, HIPAA, high volume, dedicated support.
Custom
Knock
Developer
Free forever. 10K messages, 500 guide users, 500 AI credits/month.
$0 base (usage-based)
Starter
$250/mo. 50K messages, 2.5K guide users, 2K AI credits. Remove branding.
$250/mo
Enterprise
Custom pricing. White-label, i18n, data warehouse, Datadog, SCIM, SAML, HIPAA/BAA.
Custom
Free-tier quotas head-to-head
Comparing free on Formspree vs starter on Knock.
| Metric | Formspree | Knock |
|---|---|---|
| guide users | — | 2500 users |
| guide users overage | — | $0.05/user USD/user |
| messages monthly | — | 50000 messages/mo |
| messages overage | — | $0.005/message USD/message |
Features
Formspree · 11 features
- Custom Success Redirect — Redirect after submit.
- Email Notifications — Submissions delivered to inbox.
- File Uploads — Accept attachments (Unlimited).
- IP Filtering — Block spam IPs.
- React SDK — Hooks + state management.
- Rules Engine — Conditional routing, auto-responders.
- Spam Protection — Honeypot + reCAPTCHA + keyword filter.
- Submission Analytics — Volume + source stats.
- Team Members — Multi-user (Unlimited).
- Webhooks — POST submissions to your server.
- Zero Backend — HTML <form action> → email.
Knock · 13 features
- AI Agents — Autonomous notification drafting & workflow generation.
- Batch + Digest — Group notifications into digests on schedule or window.
- Chat — Slack, Microsoft Teams, Discord.
- Email — Send via SendGrid/Postmark/Resend/Mailgun/AWS SES as relays.
- Guides — In-product messaging, announcements, modals, banners.
- i18n / Localization — Translate templates by user locale.
- In-App Feed — Notification inbox with React/Vue/iOS/Android drop-in components.
- Multi-tenancy — Per-tenant branding, preferences, quiet hours.
- Outbound Webhooks — Subscribe to delivery events.
- Preferences — User + tenant preference center with granular controls.
- Push — iOS (APNs), Android (FCM), Expo, Web Push.
- SMS — Twilio, MessageBird, Telnyx, Vonage as providers.
- Workflows — Visual notification orchestration (branch, batch, delay, throttle).
Developer interfaces
| Kind | Formspree | Knock |
|---|---|---|
| CLI | — | Knock CLI |
| SDK | @formspree/core, @formspree/react | knockapi (Python), knockapi (Ruby), knock-elixir, knock-go, knock-java, @knocklabs/node, @knocklabs/react |
| REST | Formspree REST API | Knock REST API |
| MCP | — | Knock MCP Server |
| OTHER | Direct HTML Form Submit, Formspree Dashboard, Formspree Webhooks | Outbound Webhooks |
Staxly is an independent catalog of developer platforms. Some links to Formspree and Knock may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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