They Sent It

How many brand emails carry dark mode code? 73,545 emails, October 2026

Published November 13, 2026 · Emails sent October 1 to 31, 2026 · Scanned November 13, 2026. Download CSV

We scanned the latest October 2026 email from each of 73,545 published brands for dark mode code. What the code does and how to use it: Dark mode and How to fix dark mode in email.

Findings

  1. 0.8% carried the exact light only tag, the Gmail opt-out.
  2. 96.8% carried none of the four signals we searched for.
  3. 1.0% included dark styles (the brand's or its template's).
  4. 93 emails sent both the opt-out and dark styles, which can conflict in Apple Mail on the Mac.

Dark mode signals in the code

Share of emails with each signal. An email can have several.

Dark mode signals, 73,545 emails
SignalEmailsShare
Color modes declared in HTMLA color-scheme meta tag, any value.2,0312.8%
Light only: the Gmail opt-outThe exact value light only, which the Gmail app is reported to honor for Google accounts.5590.8%
Light mode declaredThe value light. It does not stop Gmail's forced dark mode.7261.0%
Light and dark declaredThe value light dark, in either order.5470.7%
Dark mode declaredThe value dark. It does not mean dark styles exist.1280.2%
Only light (unconfirmed)Valid CSS, but not confirmed to work in Gmail.460.1%
Color modes declared in CSSThe CSS color-scheme property, any value.1,1471.6%
Dark styles includedA prefers-color-scheme: dark query, from the brand or its template.7001.0%
Outlook fixes includeddata-ogsc or data-ogsb selectors, which restore colors Outlook rewrites.5080.7%
None of the four signalsNo color-scheme tag, no color-scheme in CSS, no dark styles, no Outlook selectors.71,18696.8%
Opt-out plus dark stylesBoth the light only tag and a dark styles query. We did not count how many also declare light dark in CSS.930.1%

By email platform

Platforms with at least 100 brands; 317 emails on smaller platforms left out
PlatformEmailsColor-scheme meta tagLight onlyDark stylesOutlook selectors
Klaviyo62,1492.9%0.83%0.9%0.7%
Mailchimp6,8041.8%0.35%0.9%0.7%
HubSpot3,2951.9%0.49%1.2%0.6%
ActiveCampaign7183.9%0.42%1.0%1.7%
Omnisend1371.5%0.73%0.7%0.7%
Shopify Email1250.8%0.00%0.0%0.0%

Small groups swing on a few emails: ActiveCampaign's light only share is 3 emails. Platform is the brand's, not the email's.

By how often the brand sends

Brands grouped by their emails a week on They Sent It
SendsEmailsColor-scheme meta tagLight onlyDark styles
Under 2 a week28,5962.4%0.67%0.7%
2 to 5 a week37,2073.0%0.83%1.0%
5 or more a week7,7422.6%0.76%1.3%

Emails with the light only tag, shown as sent.

Emails with dark styles and no light only tag. Apple Mail and others switch these to their dark version.

Method

Sample
One email per published brand: its latest campaign sent October 1 to 31, 2026, US Eastern. Automated emails are left out. Klaviyo brands are 84.5% of the sample.
Our own data
Sent to addresses we subscribed ourselves, so it is what a new subscriber gets. Segmented sends are undercounted.
What we looked for
On November 13, 2026 we searched each email's HTML for the four signals in the table. A match anywhere counts. We cannot tell a brand's own dark styles from its platform's template.
What we cannot see
How any app displayed the email, or the brand's other October emails.
Fixed figures
From one saved scan. New emails do not change them; corrections are dated below.

How to cite

They Sent It. (2026). Dark mode code in brand email, October 2026. Retrieved from theysentit.com/research/dark-mode-2026

Emails sent October 1 to 31, 2026; scanned November 13, 2026. Add the date you read the page.

Download this dataset as CSV - counts by group (all, platform, sending frequency) and by signal. Free to reuse under CC BY 4.0 with credit, a link, and a note if you changed it.

Published November 13, 2026 by Conner Baker. Background: Dark mode in Learn. Found an error? Tell us.

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