Built-in audience
management
Collect subscribers from your forms, organize contacts with tags, and send to segments — no external mailing list service needed.
Add and import
contacts
Create contacts one at a time or bulk import up to 1,000 at once. Each contact can have a name, tags, and custom metadata.
import { Posthawk } from 'posthawk';const posthawk = new Posthawk('ck_live_...');// Add a contact from your signup formawait posthawk.contacts.create({ email: 'alice@example.com', name: 'Alice', tags: ['newsletter', 'beta-users'],});// Bulk import contactsawait posthawk.contacts.import([ { email: 'bob@example.com', tags: ['newsletter'] }, { email: 'carol@example.com', tags: ['beta-users'] },]);// Send to all contacts tagged "newsletter"await posthawk.emails.send({ from: 'hello@yourapp.com', tag: 'newsletter', subject: 'Weekly Update', html: '<p>Here is your weekly update...</p>',});// Unsubscribed contacts are automatically// excluded — no manual filtering needed.Send to a tag,
reach everyone
Replace hardcoded recipient lists with tags. One API call sends to all contacts with that tag — unsubscribed contacts are automatically excluded.
Capture subscribers
from any form
Add a single API call to your newsletter signup, contact form, or registration flow. Contacts are created instantly with the tags you choose.
<!-- HTML form on your website --><form id="newsletter-form"> <input type="email" name="email" required /> <button type="submit">Subscribe</button></form><script>document.getElementById('newsletter-form') .addEventListener('submit', async (e) => { e.preventDefault(); const email = e.target.email.value; await fetch('https://api.posthawk.dev/v1/contacts', { method: 'POST', headers: { 'Content-Type': 'application/json', 'X-API-Key': 'ck_live_...', }, body: JSON.stringify({ email, tags: ['newsletter'], }), }); });</script>Three steps to
audience management
Add contacts
Create contacts via API, dashboard, or capture them from your website forms with a single POST request.
Organize with tags
Tag contacts as "newsletter", "beta-users", or any custom label. Filter and manage your audience by tag.
Send by tag
Use the tag field in your send request. Posthawk resolves all contacts with that tag and delivers.
Workspace-Scoped Contacts
Every contact belongs to a workspace. Isolated data, team access, and per-workspace audience management.
Tag-Based Segmentation
Organize contacts with tags like "newsletter", "beta-users", or "onboarding". One contact can have multiple tags.
Send by Tag
Pass a tag instead of recipient addresses. Posthawk resolves the contacts and sends — unsubscribed contacts are automatically excluded.
Unsubscribe Handling
Mark contacts as unsubscribed via API. Tag-based sends automatically skip unsubscribed contacts.
Replace your
mailing list tool
Stop maintaining a separate Mailchimp or SendGrid contact list. Posthawk contacts live alongside your email sending — one platform, one API.
Newsletter signups
Capture email addresses from your website footer or signup forms. Tag as "newsletter" and send updates.
Contact forms
Save every contact form submission as a contact with metadata. Track inquiries alongside your audience.
User onboarding
Tag new signups with "onboarding" and send welcome sequences to the entire cohort.
Start building your audience
Add your first contact in seconds. Free tier includes up to 3,000 emails per month.