Articles/HTTP

HTTP vs HTTPS — What's the Difference?

HTTP transmits data in plain text between client and server; HTTPS adds a layer of TLS encryption on top of HTTP, protecting data in transit from being read or tampered with.

Published October 4, 2026

HTTP and HTTPS are the same protocol for requesting web pages; HTTPS simply wraps it in TLS encryption. That wrapper stops anyone between you and the server from reading or altering what is sent.

The concept

With plain HTTP, requests and responses travel as readable text. Anyone on the same Wi-Fi, or any router along the path, can read passwords and cookies or inject content.

HTTPS first performs a TLS handshake: the server proves its identity with a certificate signed by a trusted authority, then both sides agree on a shared secret key. After that, everything is encrypted and tamper-evident.

HTTPS gives three guarantees: confidentiality (nobody can read it), integrity (nobody can change it) and authentication (you are talking to the real domain).

HTTP: open to anyone on the path

GET /login (plain text)response (plain text)BrowseryouRoutercan read itServerexample.com
Plain HTTP — the packet is readable at every hop.

HTTPS: encrypted end to end

TLS encryptedTLS encryptedBrowseryouRoutersees noiseServerexample.com
HTTPS — the middle only sees scrambled bytes after the TLS handshake.

The TLS handshake in 4 steps

  1. Browser says hello and lists the encryption it supports
  2. Server replies with its certificate and chosen cipher
  3. Browser checks the certificate against trusted authorities
  4. Both sides derive a shared key; encrypted traffic begins

Practical examples

Check what a site is serving

curl shows the redirect most sites use to push HTTP visitors to HTTPS.

curl -I http://example.com
# HTTP/1.1 301 Moved Permanently
# Location: https://example.com/

Redirect HTTP to HTTPS in Nginx

server {
  listen 80;
  server_name example.com;
  return 301 https://$host$request_uri;
}

Tell browsers to always use HTTPS

The HSTS header makes browsers refuse plain HTTP for your domain for a year.

Strict-Transport-Security: max-age=31536000; includeSubDomains

Common mistakes

  • Loading HTTP images or scripts on an HTTPS page — browsers flag this as mixed content and may block it.
  • Letting a certificate expire, which shows visitors a full-page warning.
  • Redirecting to HTTPS but forgetting cookies need the Secure flag.
  • Believing a padlock means the site is trustworthy; it only means the connection is encrypted.

Key takeaways

  • HTTPS = HTTP + TLS.
  • It provides encryption, integrity and server identity.
  • Redirect HTTP to HTTPS and add HSTS.

FAQ

Is HTTPS slower than HTTP?

Barely. With HTTP/2 and TLS 1.3 an HTTPS site is often faster than plain HTTP.

Does HTTPS help SEO?

Yes, Google uses it as a lightweight ranking signal and browsers mark HTTP pages as Not secure.

Are certificates expensive?

No. Let's Encrypt issues free, auto-renewing certificates.

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