Générateur de clés DKIM
Generate a DKIM key pair, get the DNS record and private key it produces, or paste a record you already have and check it. The key pair is generated locally in your browser and never sent anywhere.
Qu'est-ce que DKIM ?
DKIM (DomainKeys Identified Mail) attaches a digital signature to every message you send, using a private key only your mail server knows. The receiving mailbox looks up the matching public key in your DNS and checks the signature, proof the message really came from you and wasn't altered in transit.
The key pair is generated once. The private key stays on your mail server or your email service provider, where it signs outgoing mail. The public key goes into a DNS TXT record at a location called the selector. That's the only part this tool publishes for you.
Sélecteur
A short name that lets you run more than one key at once, useful for rotating keys or running several sending services side by side.
Clé publique (DNS)
Published as a TXT record at selector._domainkey.yourdomain.com. Anyone can look it up: that's the point.
Clé privée (votre serveur)
Gardée secrète et installée là où votre courrier est effectivement signé. Ne la publiez jamais et ne l'envoyez jamais ailleurs.
DKIM on its own only proves a message wasn't tampered with. It's DMARC that decides what happens when a message fails. Once DKIM is signing cleanly, the DMARC policy generator is the natural next step.
Générez votre clé
Fill in your domain and selector, pick a key size, and generate. The DNS record on the right updates with it. Already have a record? Paste it in to check it.
Générer une paire de clés
Runs entirely in your browser. The private key is never sent anywhere.
Taille de clé
2048 bits est la recommandation actuelle. 1024 bits est plus faible mais plus court, ce qui compte si votre fournisseur DNS a du mal avec les longs enregistrements TXT.
Restreindre les hachages à SHA-256
hOnly allow SHA-256 signatures. Leaving this off also accepts the older, weaker SHA-1. Most senders should keep this on.
Restreindre à l'e-mail
sLimiter cette clé à la signature d'e-mails, afin qu'elle ne puisse pas être réutilisée pour signer autre chose qui vérifierait le tag s.
Mode test
t=yAsk receivers not to act on a signature failure yet. Useful while you roll this out. Turn it off once mail is signing and passing cleanly.
Correspondance stricte du sous-domaine
t=sExigez que le domaine de signature corresponde exactement à votre domaine From, afin que cette clé ne puisse pas être utilisée pour signer au nom d'un sous-domaine.
Clé privée
Générez une paire de clés pour voir votre clé privée ici.
Enregistrement DNS
Publiez cet enregistrement TXT sur votre domaine.
Add this as a new record at your DNS provider. “Type” and “Host” are the fields it asks for. Some providers want just mail._domainkey in the host field and add the domain for you.
Paste an existing record here to check it. It won't recover a private key.