Twilio SendGrid has successfully scaled its infrastructure to manage billions of emails reliably, quickly, and securely, including processing 4.1 billion emails on Black Friday in 2019 and 4.2 billion emails on Cyber Monday this year. To provide faster delivery times, Twilio SendGrid has introduced a new metric called "Time to First Attempt" (TFA), which measures the time it takes for an email API request to be delivered to the mailbox provider server, achieving a median TFA of 1.9 seconds over the last three months. The company's proprietary Mail Transfer Agent (MTA) enables scalability, reliability, and agility in handling billions of emails expeditiously. Twilio SendGrid has established endpoints worldwide to handle emails from various parts of the globe and uses authentication, processing, and delivery as its "secret sauce" to ensure optimal delivery. The company provides deliverability consultation services to help senders build trust with mailbox providers by following best practices such as SPF, DKIM, DMARC, email validation, and hygiene.