Yellow Lab Tools : Online test to help speeding up heavy web pages
repl.it : Powerful and simple online compiler, IDE, interpreter, and REPL. Code, compile, and run code in 30+ programming languages. including JavaScript, Pytho...
MailHog : MailHog is an email testing tool for developers:
Configure your application to use MailHog for SMTP delivery
View messages in the web UI, or retrieve ...
Bloody Vikings! : Firefox addon to simplify the use of temporary e-mail addresses in order to protect your real address from spam.
Security Headers : I built securityheaders.io after deploying security headers like CSP and HSTS to my own site. I wanted a quick and easy way to check if other sites we...
Free online service that allows you to test your emails for Spam, Malformed Content and Mail Server Configuration problems