DNS tools

DNS record splitter

Split long DNS TXT records (like DKIM keys) into 255-character segments for providers that require it. Free, instant, no signup required.

Output format:

Splits long TXT records (like DKIM keys) into 255-character segments for Google Cloud DNS, AWS Route 53, Azure DNS, and other providers that require manual splitting. Everything runs in your browser, nothing is uploaded.

How to use the DNS record splitter

Paste your long TXT record

Most commonly a 2048-bit DKIM public key, but any long TXT value works. Already-quoted records are merged and re-split automatically.

Choose the output format

Quoted for Google Cloud DNS, AWS Route 53, and Azure DNS; Plain if your provider accepts one segment per line.

Copy the formatted record

One click copies the split record, ready to paste into your DNS provider's TXT field.

Verify after publishing

DNS propagation typically takes 5-60 minutes. Then confirm the record resolves correctly with our TXT Record Checker.

Why TXT records need splitting

The 255-character limit

Per RFC 1035, a single character-string in a TXT record holds at most 255 octets. Longer values must be published as multiple strings.

Resolvers rejoin the parts

When a resolver reads a multi-string TXT record, the segments are concatenated back together, "part1" "part2" is read exactly as part1part2.

Providers differ

Google Cloud DNS and Route 53 require you to quote and split manually; Cloudflare and GoDaddy split automatically. A wrong split breaks DKIM validation.

Why correct splitting matters for email authentication

DKIM key integrity

A 2048-bit DKIM key is cryptographic data. A single missing or duplicated character means every signature fails verification.

Strict format requirements

Extra spaces, stray quotes, or characters cut off at the wrong point silently break validation, the record looks fine but never verifies.

Avoid propagation delays

Discovering a formatting error after publishing means waiting through another propagation cycle to fix it. Get it right the first time.

100% client-side

Everything runs in your browser, your record (and any key material) never leaves your device or touches our servers.

Frequently asked questions

A utility that takes a TXT value longer than 255 characters and splits it into correctly quoted segments that DNS providers accept, so resolvers can rejoin them into the original value.

Google Cloud DNS rejects long unsplit records; AWS Route 53 and Azure DNS require quoted segments. Cloudflare, GoDaddy, and Namecheap handle splitting automatically.

No. Multi-string TXT records are concatenated by resolvers, so the value received by verifiers is byte-for-byte identical to the original. Splitting is purely a storage format.

Modern 2048-bit DKIM keys produce TXT values of roughly 400+ characters, well past the 255-character string limit, so most providers require them to be split into two segments.

You should only ever publish public keys in DNS. That said, the splitter runs entirely in your browser and sends nothing to any server.

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