appsflyer.com
Good, with 3 things to fix
appsflyer.com scored 76/100 (grade B). The main issues are DKIM key shorter than 2048 bits and DMARC: subdomain policy is weaker than the domain policy, plus 1 more. Detected senders: Google Workspace.
Checked 2026-10-04 02:07 UTC · fresh check
Reduce SPF DNS lookups
Evaluating SPF for appsflyer.com takes 10 DNS lookups including nested includes; receivers stop at 10 and fail SPF. No detected sending service accounts for these includes; remove each one you no longer send through: spf.appsflyer.com. Changes: Added include:_spf.google.com for Google Workspace. Replaced ~all with -all so mail from servers not listed is rejected.
appsflyer.com
Some DNS providers want “@” here instead of the full domain.
v=spf1 ip4:167.89.0.0/17 ip4:208.117.48.0/20 ip4:50.31.32.0/19 ip4:198.37.144.0/20 ip4:198.21.0.0/21 ip4:192.254.112.0/20 ip4:168.245.0.0/17 ip4:149.72.0.0/16 ip4:159.183.0.0/16 ip4:223.165.113.0/24 ip4:223.165.115.0/24 include:spf.appsflyer.com include:_spf.google.com -all
v=spf1 ip4:167.89.0.0/17 ip4:208.117.48.0/20 ip4:50.31.32.0/19 ip4:198.37.144.0/20 ip4:198.21.0.0/21 ip4:192.254.112.0/20 ip4:168.245.0.0/17 ip4:149.72.0.0/16 ip4:159.183.0.0/16 ip4:223.165.113.0/24 ip4:223.165.115.0/24 include:spf.appsflyer.com ~all
How to apply it
- Sign in where your domain’s DNS is managed. This is often where you bought the domain, such as Cloudflare, GoDaddy or Namecheap.
- Find the existing TXT record with that name and replace its value.
- Save, then come back and re-check. DNS changes can take up to a few hours to show.
All checks
MXCan servers find your inbox?No issues foundPass
Nothing to report.
SPFWho may send as you?SPF is close to the 10-lookup limitNeeds attention
- Warning: SPF is close to the 10-lookup limit
Evaluating the SPF record for appsflyer.com needs 10 of the 10 allowed DNS lookups. Adding one more service, or a provider growing its own record, will break SPF.
How to fix this - Info: SPF ends in softfail (~all)
"~all" is common and works well with DMARC. "-all" is stricter; switch when you are sure every sender is listed.
DKIMAre your emails signed?DKIM key shorter than 2048 bitsNeeds attention
- Warning: DKIM key shorter than 2048 bits
google (1024-bit), s2 (1024-bit) uses an RSA key below 2048 bits. Short keys can be factored and some receivers treat them as weak. Rotate to a 2048-bit key at your sending provider.
- Pass: DKIM key published
appsflyer.com publishes a DKIM key under google, k2, k3, s1, s2.
DMARCWhat happens to fakes?Subdomain policy is weaker than the domain policyNeeds attention
- Warning: Subdomain policy is weaker than the domain policy
sp=none is weaker than p=quarantine, so attackers can spoof any subdomain of appsflyer.com (for example billing.appsflyer.com) even though the main domain is protected.
How to fix this - Info: DMARC policy is quarantine; consider reject
Failing mail goes to spam rather than being refused. When reports show no legitimate failures, reject gives the strongest protection.
How to fix this
AlignmentDoes it match your From?No issues foundPass
Nothing to report.
BIMICan inboxes show your logo?No BIMI recordInfo
- Info: No BIMI record
No BIMI record at default._bimi.appsflyer.com. BIMI is optional: it shows your logo next to your mail in supporting inboxes once DMARC is enforced.
How to fix this
MTA-STSIs mail to you encrypted?No MTA-STS recordInfo
- Info: No MTA-STS record
No MTA-STS record at _mta-sts.appsflyer.com. MTA-STS (RFC 8461) makes sending servers require TLS and a valid certificate when delivering to you, which blocks downgrade attacks.
How to fix this
TLS-RPTWill you hear about failures?No TLS-RPT recordInfo
- Info: No TLS-RPT record
No TLS reporting record at _smtp._tls.appsflyer.com. TLS-RPT (RFC 8460) tells senders where to send daily reports about failed encrypted deliveries to you.
How to fix this
Other fixes
Strengthen the DMARC policyTXT
Rejects mail that fails DMARC, the strongest protection against spoofing. Changes: Subdomains move one step, from sp=none to sp=quarantine.
_dmarc.appsflyer.com
Some DNS providers want just “_dmarc” here.
v=DMARC1; p=reject; sp=quarantine; rua=mailto:afit@appsflyer.com; adkim=r; aspf=r
v=DMARC1; p=quarantine; sp=none; rua=mailto:afit@appsflyer.com; ruf=mailto:afit@appsflyer.com
Publish the MTA-STS recordTXT
Tells sending servers that appsflyer.com publishes an MTA-STS policy at https://mta-sts.appsflyer.com/.well-known/mta-sts.txt. Change the id whenever the policy file changes.
_mta-sts.appsflyer.com
Some DNS providers want just “_mta-sts” here.
v=STSv1; id=202610040207
Host the MTA-STS policy filepolicy-file
Serve this file over HTTPS with a valid certificate for mta-sts.appsflyer.com. It lists your MX hosts and starts in testing mode; switch to mode: enforce once TLS-RPT reports show no failures.
https://mta-sts.appsflyer.com/.well-known/mta-sts.txt
version: STSv1 mode: testing mx: aspmx.l.google.com mx: alt1.aspmx.l.google.com mx: alt2.aspmx.l.google.com mx: alt3.aspmx.l.google.com mx: alt4.aspmx.l.google.com max_age: 604800
Set up a TLS report addressinstruction
Sending servers will report TLS failures when delivering to appsflyer.com, which you need before enforcing MTA-STS. The address must accept TLS reports; a DMARC report address does not necessarily do so.
Applies to: _smtp._tls.appsflyer.com
- Pick an address that will receive TLS reports: a mailbox you read (for example tls-reports@appsflyer.com, created first) or a TLS reporting service. 2. Publish a TXT record at _smtp._tls.appsflyer.com with the value v=TLSRPTv1; rua=mailto:<that address>.
Prepare BIMIinstruction
BIMI shows your logo next to messages in supporting inboxes, but only for mail that passes DMARC under an enforced policy.
Applies to: default._bimi.appsflyer.com
- Enforce DMARC first: p=quarantine or p=reject at 100% (no pct below 100). 2. Convert your logo to an SVG Tiny PS file and host it over HTTPS, for example https://appsflyer.com/bimi/logo.svg. 3. For Gmail and Apple Mail, obtain a VMC or CMC certificate for the logo. 4. Publish a TXT record at default._bimi.appsflyer.com with v=BIMI1, l= set to the logo URL and a= set to the certificate URL.