Sender Policy Framework (SPF) is an email authentication standard developed by AOL that compares the email sender’s actual IP address to a list of IP addresses authorized to send mail from that domain. The IP list is published in the domain’s DNS record.
As part of the whitelabel process you must create a subdomain (such as em.example.com) which is used for click and open tracking as well as in the Return-Path email header. SPF uses the domain value in the Return-Path header for the DNS lookup to determine the permitted senders for the domain.
If you have an SPF record set for your root domain (i.e. yourdomain.com), you must add:
before the all mechanism of this record. If you do not have an SPF record for your domain you must create a TXT record with the value:
v=spf1 include:sendgrid.net ~all
Do not create more than one SPF1 record for a given domain. If you need more than one SPF record, you will want to merge the additional SPF records into a single SPF record.
You cannot have more than 10 DNS lookups in your SPF record.
Already have an SPF record for your domain?
No problem. You simply need to add the SendGrid include mechanism lookup into your existing record.
For example, if your record looks like this:
v=spf1 a mx include:_spf.google.com include:spf.protection.outlook.com ~all
You would just need to add our lookup at the end of the string, before the
mechanism, like so:
v=spf1 a mx include:_spf.google.com include:spf.protection.outlook.com include:sendgrid.net ~all
Don’t want to include another hostname lookup?
If you would rather not include SendGrid’s SPF hostname lookup in your record, or perhaps you just have too many already, you can also choose to give permission to a specific IP address to send mail for your domain. This is accomplished using the ip4 mechanism.
If you have a Silver or higher level package, you can choose to specify your dedicated IP address as a lookup, meaning that only mail coming from that particular IP address will be considered a permitted sender within SendGrid for that domain. An example of such an include looks like this:
v=spf1 a mx include:_spf.google.com include:spf.protection.outlook.com ip4:18.104.22.168 ~all
If you wish to add multiple ip4 lookups (if you have an account that sends from multiple dedicated IPs, for example), simply add them into your record separated by spaces. Unlike with include:hostname lookups, a SPF1 record can have any number of ip4 includes.
Please note, the validation step in the Whitelabel Wizard will not recognize the ip4 mechanism, it will only accept
For more information on SPF best practices and syntax, check out www.openspf.org
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