HTTP vs HTTPS
HTTP vs HTTPS explained simply. What TLS actually encrypts, why HTTPS is now the default, and what the padlock icon means.
HTTP sends data in plain text that anyone on the network can read. HTTPS wraps the same HTTP traffic in TLS encryption, so the data cannot be read or tampered with in transit.
HTTP vs HTTPS at a glance
| HTTP | HTTPS | |
|---|---|---|
| Encryption | None, plain text | TLS encrypted |
| Port | 80 | 443 |
| Data integrity | Can be modified in transit unnoticed | Tampering is detectable |
| Identity verification | No way to confirm the server is genuine | Verified through an SSL or TLS certificate |
| Browser treatment | Marked as not secure | Shown with a padlock icon |
| SEO and modern requirement | Discouraged, many features are disabled | Required for most modern browser features |
When to use each
Choose HTTP when
- Realistically you should not choose plain HTTP for anything public facing today.
- It sometimes still appears in isolated internal networks with no sensitive data.
- It can appear briefly during local development before HTTPS is configured.
Choose HTTPS when
- You are handling any login, payment, or personal data.
- You want browsers to trust your site and show it as secure.
- You are building anything public facing in 2026, which is effectively all sites.
What TLS actually adds
HTTPS is not a separate protocol from HTTP. It is regular HTTP running inside a TLS encrypted connection. TLS handles three things, encrypting the data so it cannot be read in transit, verifying that the server is who it claims to be through a certificate, and detecting if the data was tampered with along the way.
Why this matters even for simple sites
Even if a site has no login or payment form, HTTP still leaves every request and response readable to anyone on the same network, including public WiFi. It also allows man in the middle attacks where someone intercepts and modifies the content. That is why browsers now actively warn users when a site is not using HTTPS.
A good technical detail to mention is the TLS handshake, where the client and server agree on encryption keys before any actual data is sent. This adds a small amount of latency on the first connection, which HTTP does not have, but it is a worthwhile trade for security.
Frequently asked questions
Does HTTPS slow down a website?
The TLS handshake adds a small amount of latency on the first connection, but modern optimizations like session resumption and HTTP 2 make the real world difference negligible for most sites.
What is an SSL certificate?
It is a digital file issued by a trusted certificate authority that proves a server's identity and provides the public key needed to establish an encrypted connection with clients.
Is SSL the same as TLS?
TLS is the modern successor to SSL. The name SSL is still used casually, but actual SSL versions are outdated and insecure. Modern HTTPS connections use TLS.
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