Is TLS 1.2 still safe to use?

Yes — TLS 1.2 is secure when configured with strong cipher suites (ECDHE key exchange and AES-GCM or ChaCha20-Poly1305 AEAD ciphers). Avoid legacy suites like RC4, 3DES, or non-AEAD modes. Most compliance frameworks (PCI-DSS 4.0, HIPAA) still accept TLS 1.2 as a minimum.

Why was TLS 1.0 deprecated?

TLS 1.0 (1999) is vulnerable to attacks such as BEAST, POODLE, and CRIME that exploit weaknesses in CBC cipher modes and the protocol's MAC-then-encrypt design. RFC 8996 (2021) formally deprecated TLS 1.0 and 1.1. All major browsers disabled them in 2020–2021.

What is the main advantage of TLS 1.3?

TLS 1.3 reduces the handshake to one round-trip (versus two for TLS 1.2) and supports 0-RTT resumption for returning clients. It also removes all legacy cipher suites, mandating AEAD and forward secrecy, which greatly shrinks the attack surface.

What does forward secrecy mean?

Forward secrecy (also called perfect forward secrecy, PFS) means each session uses a fresh ephemeral key pair. If a server's long-term private key is later compromised, past recorded sessions cannot be decrypted. TLS 1.3 requires forward secrecy; TLS 1.2 supports it optionally via ECDHE/DHE key exchange.

How do I check which TLS version my server uses?

Run: openssl s_client -connect yourdomain.com:443 -tls1_3 (or -tls1_2, -tls1_1, -tls1). A successful handshake confirms the version is enabled. Online tools like SSL Labs' Server Test also report supported versions and assign a grade.

What minimum TLS version should I require?

Configure your server to accept TLS 1.2 as the minimum and TLS 1.3 as preferred. Disable TLS 1.0 and 1.1 entirely. This satisfies PCI-DSS 4.0, NIST guidelines, and modern browser requirements while maintaining broad client compatibility.

TLS Version Reference

Name: TLS Version Reference
Availability: InStock
Author: Nham Vu

Compare TLS 1.0, 1.1, 1.2, and 1.3 side-by-side: deprecation status, supported cipher suites, and browser/server compatibility.

TLS 1.0 Deprecated

Released 1999. Formally deprecated by RFC 8996 (2021). Disabled by Chrome, Firefox, Edge, and Safari since 2020.

No forward secrecy by default
Vulnerable to BEAST, POODLE
Supports RC4, 3DES, MD5
MAC-then-encrypt design flaw

RFC 2246 (1999)

TLS 1.1 Deprecated

Released 2006. Also deprecated by RFC 8996 (2021). Addressed some CBC weaknesses but still considered insecure.

No forward secrecy by default
Partially mitigates BEAST
Still allows RC4, 3DES
Adds explicit CBC IV (minor fix)

RFC 4346 (2006)

TLS 1.2 Current (minimum)

Released 2008. Still widely deployed and acceptable when using ECDHE key exchange with AEAD cipher suites.

Forward secrecy via ECDHE/DHE
Supports AES-GCM, ChaCha20
SHA-256/384 PRF (no MD5/SHA-1)
Still allows weak suites if misconfigured

RFC 5246 (2008)

TLS 1.3 Recommended

Released 2018. Removes all legacy algorithms. Faster 1-RTT handshake and optional 0-RTT session resumption.

Forward secrecy mandatory
AEAD-only cipher suites
1-RTT handshake (2-RTT for TLS 1.2)
Encrypted handshake metadata

RFC 8446 (2018)

Full Comparison Table

Feature	TLS 1.0	TLS 1.1	TLS 1.2	TLS 1.3

Recommended TLS 1.2 Cipher Suites

Configure these in preference order. All provide ECDHE key exchange (forward secrecy) and AEAD authenticated encryption.

TLS 1.3 Cipher Suites (hardcoded)

TLS 1.3 ships exactly five cipher suites. Servers and clients negotiate which of these to use; the key exchange is always ECDHE or DHE.

Quick Reference — Test & Configure

Summary

Compare TLS 1.0, 1.1, 1.2, and 1.3 side-by-side: deprecation status, supported cipher suites, and browser/server compatibility.

How it works

Choose the TLS version you want to learn about from the version cards at the top.
Read the deprecation status badge to know at a glance whether the version is safe to use.
Review the supported cipher suites listed for each version.
Use the search box to filter the comparison table by keyword (e.g. "cipher", "forward secrecy").
Check the compatibility column to see which browsers and servers support each version.
Use the findings to decide which minimum TLS version to configure on your server.

Use cases

Auditing a server configuration to ensure TLS 1.0 and 1.1 are disabled.
Explaining TLS deprecation to non-technical stakeholders.
Choosing cipher suites when configuring Nginx, Apache, or a CDN.
Comparing handshake round-trip differences between TLS 1.2 and TLS 1.3.
Verifying which TLS versions a target browser or client supports.
Preparing for a PCI-DSS or SOC 2 compliance assessment.
Teaching developers about forward secrecy and AEAD ciphers.
Quick reference during a security code review.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu