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Color
"Color" tools
CMYK conversion
HTML Color list
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Bandwidth convert
Download calculator
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Finance
"Finance" tools
EV mileage calculator
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"Music" tools
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Tap your tempo
Photo
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Physics
"Physics" tools
Acceleration calculator
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Gladwell's 10000 hours
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Video
"Video" tools
Audio file size calculator
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Web
"Web" tools
Content Security Policy
Redirection check
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HTML char map
Emoji char map
HTML encoder
SEO Performance
URL encoder
Sender Policy Framework Check
Give the domain name as used for email addresses
domain
Check!
MX Email reception
No MX specified
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.
No SPF specified (no TXT records for this domain)
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
