130+ features built for email delivery

From transactional API to marketing automation and AI-powered optimization. Every feature you need to send, track, and improve email at scale.

Email Delivery

High-performance email infrastructure built on KumoMTA with intelligent routing and real-time monitoring.

REST API & SMTP Relay

Send emails via RESTful API or standard SMTP. Sub-12ms API latency with automatic failover. Batch sending supports up to 10,000 recipients per request.

Open & Click Tracking

Pixel-based open tracking and link-level click tracking. Custom tracking domains for brand consistency. Real-time event webhooks.

Bounce Processing

Automatic bounce classification with 50+ bounce codes. Hard bounces auto-suppressed, soft bounces retried with exponential backoff. FBL processing built in.

DKIM, SPF & DMARC

Auto-generated DKIM keys with 3-layer defense (memory, filesystem, HTTP fallback). SPF and DMARC record generation. No unsigned email ever leaves the system.

Marketing Automation

Visual workflow builder for drip campaigns, triggers, and multi-step automations.

Visual Campaign Builder

Drag-and-drop workflow designer with branching logic, time delays, and conditional splits. Preview the entire journey before launching.

Drip Campaigns

Timed email sequences with dynamic content. Trigger campaigns based on user actions, properties, or external events via API.

A/B Testing

Test subject lines, content, send times, and sender names. Automatic winner selection based on open rate, click rate, or conversion.

Smart Scheduling

AI-powered send-time optimization per recipient. Timezone-aware delivery windows. Throttling to protect sender reputation during warmup.

Contact Management

Unified contact profiles with segments, tags, and custom fields for precise targeting.

Dynamic Segments

Build segments with AND/OR conditions on any contact property, behavior, or event. Segments update in real-time as contacts change.

Lists & Tags

Organize contacts into lists and apply unlimited tags. Bulk operations with CSV import supporting 500K+ contacts per upload.

Custom Fields

Add unlimited custom fields with types: text, number, date, boolean, dropdown, and JSON. Use custom fields in templates and segments.

Contact Import & Export

CSV and JSON import with field mapping and deduplication. Background processing for large files. Export any segment to CSV.

Multi-Channel Messaging

Reach customers on their preferred channel: email, SMS, WhatsApp, or web push.

SMS Messaging

Twilio-powered SMS with A2P 10DLC registration support. Two-way messaging, keyword triggers, and delivery receipts. Global coverage.

WhatsApp Business

Meta Cloud API integration with template message management. Rich media support, interactive buttons, and conversation tracking.

Web Push Notifications

VAPID-based web push with subscription management. Segmented push campaigns with rich content, images, and action buttons.

Cross-Channel Orchestration

Build automations that span multiple channels. Fallback logic: if email not opened, send SMS. Unified analytics across all channels.

AI Features

Self-hosted AI models for content generation, optimization, and insights -- no data leaves your infrastructure.

Subject Line Generator

AI generates high-performing subject lines based on your audience and content. A/B test AI suggestions against your own to continuously improve.

Content Writer

Generate email body copy from prompts or outlines. Maintains your brand voice with custom style training. Supports multiple languages.

Send-Time Optimizer

Machine learning model predicts optimal send time per recipient based on historical engagement patterns. Improves open rates by up to 23%.

Spam Score Predictor

Pre-send spam analysis using Rspamd and SpamAssassin engines. Get actionable recommendations to improve inbox placement before you hit send.

Analytics & Reporting

ClickHouse-powered real-time analytics with custom dashboards, KPI tracking, and export.

Real-Time Dashboards

Monitor delivery, bounces, opens, clicks, and unsubscribes in real-time. Domain-level, campaign-level, and contact-level drill-down.

Custom Reports

Build custom reports with any combination of metrics and dimensions. Schedule automated report delivery to stakeholders.

Geographic Analytics

See where your emails are opened on an interactive map. Track engagement by country, region, and city for localized campaigns.

Deliverability Monitoring

Track inbox placement across major ISPs. Domain reputation scoring, blacklist monitoring, and automated recovery workflows.

Security & Compliance

Enterprise-grade security with encryption, RBAC, audit logging, and compliance features.

Encryption & DKIM

TLS 1.3 for all connections. DKIM signing on every outbound email with automatic key rotation. S/MIME certificate support.

Role-Based Access Control

Fine-grained permissions with custom roles. Separate admin, sender, analyst, and viewer roles. Multi-factor authentication required.

Audit Logging

Every action logged with user, timestamp, and IP address. Immutable audit trail for compliance. Export to SIEM systems.

GDPR & CAN-SPAM

Built-in consent management, unsubscribe handling, and data retention policies. One-click contact data export and deletion.

Developer Tools

SDKs, CLI, webhooks, and comprehensive API documentation for seamless integration.

SDKs & Libraries

Official SDKs for Go, Node.js, Python, PHP, Ruby, and Java. Type-safe with full IDE autocomplete. Available on npm, PyPI, and pkg.go.dev.

CLI Tool

Command-line interface for managing domains, sending test emails, viewing logs, and deploying templates. Scriptable for CI/CD pipelines.

Webhooks

Real-time event webhooks for delivery, bounce, open, click, and unsubscribe events. HMAC-signed payloads with dead-letter queue and retry.

API Documentation

Interactive API reference with code examples in 6 languages. Postman collection and OpenAPI 3.1 specification included.

Start building with Flowvaro today

1,000 free emails per month. Full API access. No credit card required.