HTTP vs HTTPS performance

Question

Are there any major differences in performance between http and https? I seem to recall reading that HTTPS can be a fifth as fast as HTTP. Is this valid with the current g

Answer 1

The HTTPS indeed affects page speed...

The quotes above reveal the foolishness of many people about site security and speed. HTTPS / SSL server handshaking creates an initial stall in making Internet connections. There’s a slow delay before anything starts to render on your visitor’s browser screen. This delay is measured in Time-to-First-Byte information.

HTTPS handshake overhead appears in Time-to-First-Byte information (TTFB). Common TTFB ranges from under 100 milliseconds (best-case) to over 1.5 seconds (worst case). But, of course, with HTTPS it’s 500 milliseconds worse.

Roundtrip, wireless 3G connections can be 500 milliseconds or more. The extra trips double delays to 1 second or more. This is a big, negative impact on mobile performance. Very bad news.

My advice, if you're not exchanging sensitive data then you don't need SSL at all, but if you do like an ecommerce website then you can just enable HTTPS on certain pages where sensitive data is exchanged like Login and checkout.

Source: Pagepipe