The SendPing journal
Guides and practical notes on email automation, deliverability, and building reliable delivery into your product.
Latest articles
Gmail Email Forwarding: Setup, Filters and Delivery Checks
Set up Gmail email forwarding, verify the destination, test selective filters and diagnose missing copies with a practical delivery checklist.
How to Stop Spam Emails in Gmail: A Practical Inbox Cleanup Guide
Reduce unwanted Gmail messages with the right spam, unsubscribe and block controls. Find the Spam folder and distinguish junk from phishing and wanted mail.
What Is Amazon Simple Notification Service? SNS, Queues and Email
Understand Amazon SNS, compare SNS with SQS and SES, and design a report notification workflow with duplicate handling and clear delivery evidence.
DKIM Check: Verify the DNS Record and the Actual Email
Run a DKIM check using the real message selector, DNS records and receiver results. Diagnose missing signatures, failed verification and DMARC alignment.
How to Send Email from a Webhook Without Duplicates or Feedback Loops
Build a webhook-triggered email workflow with signature verification, durable event admission, an outbox, bounded retries and clear delivery states.
Custom Email Tracking Domains: Setup, Link Safety and Troubleshooting
Understand custom tracking domains, DNS roles, verification, historical links and the limits of open and click events before changing your setup.
Recurring Emails: Time Zones, Reliable Scheduling and Duplicate Prevention
Design recurring email schedules with named time zones, occurrence records, daylight-saving policies, cancellation and durable retries.
Resend vs Postmark, Mailgun and Loops: Compare the Email Workflow
Compare Resend, Postmark, Mailgun and Loops by current entry plans, message workflows, audience billing and a practical migration pilot.
How to Choose a Notification Service for Email, Push and In-App Messages
Compare notification channels, Firebase Cloud Messaging, OneSignal and email APIs through identity, preferences, delivery behavior and operating cost.
Email API Comparison: Resend, SendGrid and MailBlastr
Compare current Resend, SendGrid and MailBlastr entry plans, interface support, daily limits and the operational tests needed before moving email traffic.
Resend Verification Emails: Timers, Retries and Clear Account States
Design a verification-email resend flow with server-enforced limits, clear challenge states, durable sends, idempotent retries and useful support records.
SMTP Settings Explained: Host, Port, Credentials and Connection Errors
Find the right SMTP host, port, encryption and credentials, diagnose failures by stage, and understand when your application needs an email API.
Email Verification APIs: Compare Results, Uncertainty and Integration
Evaluate email verification APIs with an authorized test set, compare Hunter and ZeroBounce status handling, and separate validity from ownership and consent.
Supabase Custom SMTP: Configure Auth Email and Test the User Journey
Configure Supabase Auth email with an appropriate SMTP provider or email hook, then test confirmation, recovery and changed-address flows.
Email Consent Records: Keep the Permission, Purpose and Opt-Out Together
Keep email permission, purpose, evidence and opt-out state together so campaigns respect the latest applicable subscriber preferences.
Dedicated vs Shared Email IPs: Choose Around Your Sending Pattern
Compare dedicated and shared email IPs using volume, consistency, operational ownership and delivery evidence rather than inbox promises.
Scheduled Email Delivery: Store the Time, Content and Cancellation State
Design scheduled email delivery around explicit time zones, current eligibility, cancellation and a verified provider handoff.
Email Sender Avatars and BIMI: Separate Branding From Delivery Authentication
Understand email sender avatars and BIMI, separate visual branding from authentication and check mailbox-provider requirements.
Inline Email Images: CID Attachments, Hosted URLs and Reliable Fallbacks
Compare CID attachments and hosted email images, match content IDs correctly and keep messages useful when recipients block remote images.
DMARC Policy and Subdomains: Move From Monitoring to Enforcement Carefully
Review DMARC policy, subdomain handling and current specification changes before moving from monitoring to enforcement.
Sending Email With Django: Configuration, Tests and Durable Delivery
Configure Django email, test messages without external delivery and move production sending into a reliable workflow with explicit failure handling.
PHPMailer and SMTP: A Deployment Checklist With a Minimal Example
Configure PHPMailer with SMTP using a minimal example and a deployment checklist for credentials, encryption, sender identity and error handling.
Sending Email From Node.js: Separate the Request From the Send
Build a Node.js email workflow with safe message previews, SMTP configuration, durable jobs and clear handling of retries and delivery outcomes.
How to Read a DMARC Report and Investigate Unexpected Senders
Read DMARC aggregate reports, investigate unfamiliar senders and distinguish alignment problems from legitimate mail that needs configuration.
Opportunistic and Enforced TLS: Know Which Email Connection You Are Protecting
Understand opportunistic and enforced email TLS, distinguish submission from server delivery and check the connection your policy protects.
Email Bounces: Diagnose the Response Before Retrying
Interpret email bounce responses, distinguish temporary from permanent failures and build a retry process that protects delivery reliability.
Why Emails Go to Spam: A Sender’s Diagnostic Checklist
Diagnose email spam placement by checking authentication, recipient expectations, sending patterns and message quality in a practical sequence.
Email Domain Not Verifying: Trace the DNS Record That Is Wrong
Trace failed email domain verification through authoritative DNS, exact hostnames, record types, conflicting entries and cached answers.
React Email Templates: Build a Reusable Transactional System
Build reusable React Email layouts, render HTML and plain text, test realistic fixtures and version each template used by your send workflow.
From, Reply-To and Return-Path: Which Address Does What?
Understand which email address identifies the sender, receives replies and handles bounces, with MailBlastr configuration and testing guidance.
Email Subject-Line A/B Tests: Choose a Useful Outcome
Design subject-line tests with stable assignments, comparable messages and meaningful outcomes, while reporting uncertainty and open-rate limits.
Email Dark Mode: A Testing Plan for Transactional Templates
Build transactional emails with readable dark-mode fallbacks, resilient images and buttons, and a focused test matrix for real inbox clients.
Email Preheaders: Examples That Work With the Subject Line
Write useful preheaders that complement the subject, protect private information and survive different inbox previews, with practical examples.
Apple Private Relay Email: What App Developers Need to Handle
Support Sign in with Apple relay addresses with registered sender sources, correct authentication and practical tests for delivery and replies.
Email Rate Limiting: Queue Work Without Overloading Your Provider
Control email dispatch across workers, classify throttling responses, preserve idempotency and monitor queue age for time-sensitive messages.
Email Attachments: Size, File Safety and Link-Based Alternatives
Understand attachment size overhead, MailBlastr acceptance limits, recipient constraints and when a controlled download link is a better fit.
An Email Provider Migration Checklist With a Rollback Plan
Move email providers while preserving preferences, suppressions, notification identities, delivery events and a rollback path that avoids duplicate sends.
SaaS Welcome Emails: Five Examples With a Clear Next Step
Use five original SaaS welcome email patterns for new workspaces, invitations, imports, setup preferences and the first completed task.
Password Reset Emails: A Reliable Delivery and UX Checklist
Build a password reset email flow with clear copy, safe token handling, predictable retries and tests that cover expired links and delivery delays.
Why Email Open Rates Are No Longer a Reliable Success Metric
Understand why recorded opens can differ from human reads, and build email reporting around delivery health and meaningful customer actions.
Email Suppression Lists: Keep Opt-Outs Intact Across Imports
Keep suppression reasons and topic preferences intact during imports, migrations and queued sends, with practical checks for MailBlastr workflows.
Sending Subdomains: Separate Email Streams Without Breaking DNS
Set up a sending subdomain with clear ownership, correct authentication records and a verification process that preserves your existing email service.
Email API Key Security: Scope, Rotate and Keep Keys Server-Side
Keep email API keys server-side, select the right permissions and plan a verified rotation that protects both account security and message delivery.
Email Webhook Retries: Handle Duplicates and Out-of-Order Events
Handle email webhook retries with signature verification, durable event storage, deduplication and explicit rules for out-of-order events.
A Transactional Email Testing Checklist Before You Ship
Test email triggers, recipients, templates, links, retries and delivery events before shipping a transactional notification workflow.
Email Says Delivered but Was Not Received: A Diagnostic Checklist
Trace a missing email from provider receipt to mailbox handling using message IDs, delivery events, recipient checks and a careful resend decision.
Email Idempotency: Stop Retries From Sending Duplicate Messages
Design reliable email retries with stable notification identities, saved payloads, provider idempotency keys and honest handling of uncertain outcomes.
Transactional vs Marketing Email: Purpose, Preferences and Delivery
Separate transactional and marketing email by purpose, manage subscription preferences and enforce the right rules across templates and queues.
Email API vs SMTP: Choose the Right Sending Interface
Compare email APIs and SMTP using authentication, structured responses, application integration and delivery-event handling.
Send Email with Next.js: A Safe Server-Side Setup
Send email from Next.js with a server-only MailBlastr helper, stable idempotency keys, authorized recipients and delivery-event tracking.
One-Click Unsubscribe: Implement and Test RFC 8058
Understand one-click unsubscribe headers, recipient-specific tokens, subscription scope and the checks that keep queued marketing mail consistent.
SPF, DKIM and DMARC Explained: Configure and Diagnose Email
Understand SPF, DKIM and DMARC alignment, inspect delivered messages and diagnose authentication failures before strengthening your domain policy.
Email Domain Warmup: Build a Measured Sending Plan
Plan email domain warmup around real recipients, authentication, consistent sending and observable outcomes instead of fixed-volume promises.
Email Webhooks: Track Delivery and Handle Events Reliably
Build a reliable email webhook receiver with signature verification, durable storage, duplicate handling and useful delivery-state tracking.
Best Transactional Email Services: A Practical Selection Guide
Compare transactional email services by integration, failure recovery, delivery visibility and operating cost, then test your critical messages.
How to Reduce Email Bounce Rate with Better Diagnostics
Diagnose email bounces, measure rates consistently, improve address collection and apply suppression rules to immediate and scheduled messages.