The email API for sending, inbound, and privacy
Send transactional emails, process inbound messages, protect user privacy with masked addresses. One API.
Transactional Email API
Send transactional emails with a simple HTTP request. Track delivery, bounces, and complaints in real time.
curl -X POST https://api.postscale.io/v1/send \
-H "Authorization: Bearer ps_live_..." \
-H "Content-Type: application/json" \
-d '{
"from": "hello@yourapp.com",
"to": ["user@example.com"],
"subject": "Welcome!",
"html_body": "<h1>Hello World</h1>"
}'Complete Email Infrastructure
Everything you need for email
Three products, one platform. Send transactional emails, process inbound messages, and protect user privacy — all through a single API.
Transactional Email Delivery
Send transactional email with authentication, delivery webhooks, and developer-friendly APIs.
High Deliverability
Authentication, suppression handling, and warming tools that support healthy inbox placement.
Simple API
Send emails with a single API call. RESTful endpoints, HTTP examples, and comprehensive documentation.
Delivery Event Webhooks
Track delivered, bounced, deferred, and complained events as Postscale processes delivery logs, DSNs, and feedback-loop reports.
Template Support
Create and manage email templates with dynamic variables. Version control and A/B testing built-in.
Dedicated IPs
Get dedicated IP addresses for full control over your sending reputation. Available on Scale and Enterprise plans.
Automatic Retries
Failed deliveries are retried automatically with exponential backoff, reducing manual recovery work.
Inbound Email Processing
Parse incoming emails and deliver them to your application via webhooks. Build support systems, reply detection, and email-powered workflows.
Webhook Delivery
Receive parsed emails as JSON via webhooks, with automatic retries and signature verification.
Full Parsing
Extract headers, body (HTML and plain text), attachment metadata, and download links. Clean JSON output ready for your app.
Attachment Handling
Attachments are stored outside webhook retries and exposed through authenticated Postscale download URLs.
Routing Rules
Filter and route emails by sender, domain, subject, headers, or SPF/DKIM results. Supports regex, AND/OR logic, and actions like forward, drop, or store.
Threading Support
Automatic thread detection using In-Reply-To and References headers. Keep conversations organized.
Spam Filtering
Built-in spam detection with configurable thresholds. Keep your inbox clean and your app secure.
DMARC Reports
Automatic DMARC aggregate report collection and analysis. See who sends email as your domain and track DKIM/SPF alignment rates.
Privacy & Masked Emails
Protect user privacy with masked email addresses. Create aliases that forward to real addresses while keeping identities hidden.
Masked Addresses
Generate unique email aliases for each user or service. Real email addresses stay private and protected.
Reply from Alias
Users can reply from their masked address. Outgoing emails are automatically rewritten to maintain privacy.
Per-User Controls
Enable, disable, or delete aliases individually. Give users full control over their masked addresses.
Custom Domains
Use your own domain for masked addresses. Maintain brand consistency while protecting privacy.
Forwarding Destinations
Forward each alias to one or more destination addresses without exposing the real inbox.
Alias Activity
Track per-alias usage and disable noisy or abused aliases from the dashboard or API.
Platform Features
Built for developers, designed for scale. Every feature you need to build reliable email infrastructure.
Global Infrastructure
EU/EEA-hosted primary service data, with a standard GDPR DPA. Multi-region availability is documented separately.
API-First
RESTful API with comprehensive documentation and HTTP examples for common languages.
Reliable Infrastructure
Redundant systems, active monitoring, and a 99.9% uptime target for production email workloads.
Security First
TLS, webhook signatures, API key controls, and audit logs for operational workflows.
Why Postscale?
A single API for transactional email, inbound processing, and privacy-focused aliases.
| Feature | Mailgun | SendGrid | SimpleLogin | Postscale |
|---|---|---|---|---|
| Transactional Email | ✓ | ✓ | — | ✓ |
| Inbound Webhooks | ✓ | ✓ | — | ✓ |
| Inbound Rules | ✓ | — | — | ✓ |
| Masked Emails | — | — | ✓ | ✓ |
| Reply from Alias | — | — | ✓ | ✓ |
| Single Unified API | — | — | — | ✓ |
| Per-Alias Controls | — | — | ✓ | ✓ |
| DMARC Reports | — | — | — | ✓ |
Built for your stack
Email infrastructure maps differently depending on what you're building. Here's how teams in each space use Postscale.
For SaaS
Transactional mail, inbound support inboxes, and masked privacy addresses behind one API key.
For e-commerce
Order confirmations, shipping updates, return RMAs, and XRechnung-compliant B2B invoicing in one platform.
For healthtech
Patient reminders and communication workflows with EU/EEA-hosted primary service data and a standard GDPR DPA.
Compliance documents
Review Postscale's standard DPA, current subprocessors, and privacy terms before moving production mail.
Free email tools
Quick-diagnosis utilities we use every time we onboard a customer. Point them at any domain or paste any record — nothing is uploaded to our servers.
SPF record checker
Walk the include/redirect tree, count lookups against the 10 limit.
DKIM record lookup
Selector + domain → parsed TXT, key size estimate, weak-key warnings.
DMARC policy checker
Fetch DMARC, score enforcement 0–5, recommend next steps.
DMARC aggregate parser
Paste RUA XML → per-source records, alignment, pass rate.
Email headers analyzer
Paste raw headers → routing hops, timing, SPF/DKIM/DMARC pills.
Migration converter
Convert provider snippets, SMTP settings, and suppression CSVs.
Ready to get started?
Join developers who trust Postscale for their email infrastructure. Start free, scale as you grow.