Welcome · Studio
Overall compatibility: 96/100 across 21 email clients · 20 of 21 clients passing (7 clean at 100%) · 123 compatibility warnings (0 error-level) · 16.2KB compiled HTML.
Attribution · React Email
Template adapted from the open-source React Email collection under the MIT License (© Plus Five Five, Inc. / Resend). Full React source code is included.
Client Compatibility
Score: 96/100 · 20/21 passing
Notes on this template
It opens: "Welcome to Halo ,set up your ring in minutes Meet the ring that thinks with you Discover Halo Hands-free help from day one Your personal AI companion, wrapped around your finger. More than jewelry, it's a quiet AI partner on...". Preheader: "Welcome to Halo". 7 images, 4 Outlook-only blocks, no dark-mode query, web font.
The spread is what matters on this template: 100 in Superhuman against 70 in Outlook Classic, a 30-point gap across the same file. 7 of the 21 clients render it without a single flagged property. Outlook Classic is the one to preview against after any edit, because it is where this template has the least margin, and the 123 warnings behind that score are concentrated there rather than spread evenly.
At 16.2KB compiled it has roughly 86KB of headroom before Gmail clips the message at 102KB and hides the rest behind a "View entire message" link. Inlined CSS and base64 images both count toward that, so watch it as you add sections.
Safe to customise: The opening line and the single call to action. A welcome is opened once, usually within minutes, and the reader is deciding whether the product is worth a second visit, so name the one thing you want them to do and cut the rest.
Leave alone: The button construction. It is a table cell with padding rather than a styled anchor, which is what keeps the whole shape clickable in Outlook. Swap in a padded <a> and the hit area shrinks to the text itself.
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