What is the maximum DMARC record length?
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Ever copied a DMARC record into your DNS and wondered if it's actually going to fit? Here's the thing: DNS has a hard limit of 255 characters per string in a TXT record. Your DMARC record can absolutely exceed that, but you'll need to split it across multiple quoted strings.
It's simpler than it sounds. If your record hits the limit, you just break it into chunks like this: "first-chunk" "second-chunk" "third-chunk". Each chunk stays under 255 characters, and the DNS system reads them as one record. Most DMARC records stay pretty compact (usually under 200 characters), so you won't hit this issue unless you're adding tons of reporting addresses or complex subdomain policies.
Next step: use the DMARC Parser to check if your current record's syntax is valid and see exactly how long it is.
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