Science & Technology

Q-Day: when will quantum computers break all encryption ?

By T.K. Randall
January 28, 2026 ·  1 comment

Image: IBM Q system
Credit: IBM Research / CC BY 2.0 (adapted) Back in 1999, the world braced for the impact of the so-called Millennium bug - a flaw in the date system of many computer systems that was predicted to cause widespread failures and mayhem.

Fortunately, very little happened, but there actually happens to be another possible digital catastrophe waiting in the wings - one with the potential to cause the catastrophic collapse of any digital system that uses encryption for its security.

Typically referred to as Q-Day, this little-known future event is basically the point at which quantum computers will be able to crack even the most secure digital encryption - opening all of the world's most sensitive accounts and files up for the taking.

The only protection from this will be to switch over to some sort of post-quantum protection - a security mechanism designed specifically to be immune to quantum cracking.In many ways, this scenario echoes the Millennium bug, but unlike its turn-of-the-century counterpart, this one could be far more devastating if appropriate steps are not taken well in advance.

With quantum computers currently advancing in leaps and bounds, expert opinions are mixed on exactly how long it will be before such machines can crack modern-day encryption.

Some believe that it could happen as early as 2028, while others suggest that the mid-2030s or even the mid 2040s are more realistic estimates.

Whatever the case, Q-Day is coming and it will change how we save and secure our personal data, our bank accounts and much more besides.

Source: Mail Online | Comments (1)

Tags: Quantum Computers, Encryption