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Acceleration calculator
Distance calculator
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Gladwell's 10000 hours
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"Color" tools
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"Music" tools
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Tap your tempo
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"Photo" tools
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"Video" tools
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Web
"Web" tools
Content Security Policy
Redirection check
Security Policy Framework check
HTTPS config check
HTML char map
Emoji char map
HTML encoder
SEO Performance
Network
Security Policy Framework check
Sender Policy Framework Check
Give the domain name as used for email addresses
domain
Check!
MX Email reception
aspmx.l.google.com
alt1.aspmx.l.google.com
alt2.aspmx.l.google.com
alt3.aspmx.l.google.com
alt4.aspmx.l.google.com
Sender Policy Framework
SPF
(Sender Policy Framework) is an email authentication method designed to detect forging sender addresses during the delivery of the email. With SPF, there is an exhaustive list defined of the server IP addresses that are allowed to send emails for @domain.com addresses.
v=spf1 include:_spf.google.com ~all
SPF Version:
v=spf1
SPF policy for
@google.com
addresses is defined in
_spf.google.com
: Email provider: Gmail/GSuite (Google)
Examples
SPF: @amazon.com
SPF: @apple.com
SPF: @azure.com
SPF: @facebook.com
SPF: @gmail.com
SPF: @google.com
SPF: @googlemail.com
SPF: @icloud.com
SPF: @instagram.com
SPF: @microsoft.com
SPF: @nytimes.com
References
Sender Policy Framework
Open-SPF