Everything you need to set up authentication, test your emails, and optimize campaigns — all free, all running in your browser.
Scan your email copy for spam trigger words and get a score before you hit send.
Get a 0-100 score on your subject line with feedback on length, spam words, and readability.
Select your email providers and build a valid SPF TXT record ready to paste into DNS.
Configure policy, reporting, and alignment options to generate a DMARC DNS record.
Generate RSA key pairs and DKIM DNS records entirely in your browser. Nothing leaves your machine.
Create a BIMI DNS record so your brand logo shows up next to your emails in the inbox.
Generate the DNS record and policy file to enforce TLS encryption on incoming mail.
Build a professional HTML email signature with live preview. Copy and paste into any email client.
Paste raw headers to trace the delivery path, check authentication, and spot delays.
Plug in your list size, rates, and costs to calculate revenue, profit, and ROI percentage.
Enter sample sizes and conversions to check if your email A/B test results are statistically significant.
See how your subject line and preheader look in Gmail, Apple Mail, and Outlook before sending.
Convert MJML blocks into responsive email HTML and preview the output instantly.
Generate lightweight inline SVG icons for email templates and copy ready-to-use snippets.
Find high-performing send windows by combining audience type, goal, and historical campaign data.
Audit your email HTML for accessibility issues like missing alt text and weak link labels.
Preview your email at mobile, tablet, and desktop widths to catch responsiveness problems early.
Run structural checks on AMP for Email markup before full provider validation.
Generate Schema.org JSON-LD snippets for email actions and order update messages.