Orbit web apps
Orbit web apps
Read the text-forward balance of an email before you send it. Runs entirely in your browser.
Parsed in your browser only. Nothing is uploaded, stored or sent anywhere — close the tab and it's gone.
Why the balance matters
An all-image email is the classic way to hide copy from a content scanner, so filters distrust it — and clients that block images show your reader empty boxes. A text-forward build (the rule of thumb is roughly 60% text) reads as a normal message. The percentages here are indicative, not a spam score: deliverability is reputation-driven. Email deliverability has the wider picture.
Paste email HTML to read the text-to-image balance.
The text-to-image balance of an email is one of the few deliverability signals you can see before you send. It won't predict the inbox — nothing in an HTML string does that, because deliverability is reputation-driven — but it catches the avoidable version of the mistake: a beautiful, entirely-image email that a content filter reads as a message with something to hide.
The reason an all-image email is treated with suspicion is mechanical, not aesthetic. Spam filters scan the text of a message for signals. If the entire message is a single exported image — the copy, the offer, the call to action all baked into a JPEG — there is no text to scan, which is precisely how a spammer hides a message from a content filter. The filter can't tell your polished campaign from that, so it leans cautious.
The rough guideline people cite is roughly 60% text to 40% image, and it is a guideline, not a threshold anyone published as law. What matters is the direction: enough live HTML text that the message reads as a normal email. The checker above weights each content image against the copy to give you an indicative share, and excludes the 1×1 tracking pixels and layout spacers that would otherwise inflate the image count.
A large share of inboxes don't load images until the reader clicks to show them, and some never do without a per-sender allow. For an image-only email, that means the reader's first impression is a stack of empty rectangles with broken-image icons — no headline, no offer, no reason to click.
Alt text is the fallback that shows in that gap, which is why the checker reports alt-text coverage as a first-class number rather than an accessibility footnote. A decorative image can legitimately carry an empty alt, but a content image without one is a silent hole in the message for every reader who has images off — and for every screen reader.
A well-formed marketing email is multipart: an HTML part and a text/plain part, and the receiving client picks. Most ESPs generate that plain-text part automatically from your HTML. If the HTML is all images with almost no live text, the auto-generated plain-text part is nearly empty — and a missing or empty plain-text alternative is itself a spam signal, on top of being a blank message for text-only clients and some assistive tools.
From an HTML paste alone the tool can't see the MIME structure, so it's honest about that: it tells you whether a usable plain-text part is derivable from the copy you have. Rich copy means a plain-text part that carries the message; near-zero text means one that says nothing. If you paste a full multipart source with a real text/plain section, it detects and confirms it instead.
Zero clickable links is worth catching, because a call to action rendered as a flat image isn't a link — there's nothing to click, and nothing to attribute. With Apple Mail Privacy Protection inflating open rates by pre-fetching images, clicks are the signal that actually measures an email programme, and they only exist if the buttons are real links.
At the other end, a very high link count — especially links pointing at many different domains — is one of the oldest spam tells. Legitimate for a content digest, a red flag on a simple promotional send. The checker reports both the total and the unique-domain-free count so you can tell an intentional digest from an accident.
Nothing here is a spam score. Two identical emails can land differently depending on the sending domain's reputation, the recipient's past engagement, and the provider's own model — none of which live in the HTML. Anyone selling you a single number that predicts the inbox is selling you a number.
What the checker does is remove the avoidable mistakes before they ship: the accidental all-image send, the images with no alt text, the empty plain-text part, the call to action that isn't a link. Get those right and the balance stops being the thing holding a good email out of the inbox.
Built into Orbit
Orbit's render and deliverability tooling runs this balance check as part of a wider pre-send gate — dark-mode and client rendering, image-to-text weight, alt-text coverage and auth — against your own email design system. Claude can run the gate on a draft and list exactly what to fix before it ships.
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