What Are SPF and DKIM and How Do I Set Them Up?

To keep your domain safe from misuse, you can set up email authentication. This tells receiving mail servers that your messages really come from you. In this article we’ll guide you through two common methods: SPF and DKIM.

SPF

SPF (Sender Policy Framework) is a DNS record that lists which mail servers are allowed to send email for your domain. This helps stop others from sending fake emails that look like they came from you.

DKIM

DKIM (DomainKeys Identified Mail) adds a digital signature to each outgoing email. Receiving mail servers check this signature with a public key stored in your DNS. This way they can confirm that the email really came from your domain and was not altered along the way.

Do I need to set anything up myself?

Inboxify already uses SPF and DKIM on the RETURN PATH address. This address handles bounces. For best deliverability, we recommend also setting up SPF and DKIM on the FROM address — the one your recipients see as the sender.

Setting up an SPF record

Your domain probably already has an SPF record. In that case, simply add this part:

include:_spf.inboxify.nl

If your current record is v=spf1 a mx include:spf.protection.outlook.com ~all, it becomes:

v=spf1 a mx include:spf.protection.outlook.com include:_spf.inboxify.nl ~all

Enabling DKIM signing

To enable DKIM, create a CNAME record named bm._domainkey.yourdomain.nl. Point it to dkim.inboxify.nl.

For example, if your domain is yourdomain.nl, the record will be:

bm._domainkey.yourdomain.nl CNAME dkim.inboxify.nl

The steps may vary per provider, but usually go like this:

1. Log in to your DNS management portal.
2. Open DNS settings (often called “DNS management” or similar).
3. Select your domain if you manage more than one.
4. Add a new record and choose type CNAME.
5. Enter the details:
   • Name/Label: bm._domainkey (some providers need the full subdomain, e.g. bm._domainkey.yourdomain.nl )
   • Target/Value: dkim.inboxify.nl (some providers require a trailing dot, e.g. dkim.inboxify.nl. )
6. Save the record.
7. Check after a while if the record is active. It can take minutes or a few hours.

Once the CNAME record is active, you can enable DKIM in Inboxify:

1. Click your username in the top right and choose Settings.
2. In the left menu, go to Domains.
3. You’ll see a list of your added domains.
4. If the CNAME record is correct, you can enable DKIM signing for that domain.