Home / Quantum News / What Is Q-Day? How Quantum Computers Could Break Encryption
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What I say in the video
Q-Day is the day many online secrets stop being secret.
Your messages and bank apps use digital locks.
Today, no computer can break them.
Q-Day is the day a quantum computer can break many of them.
Nobody knows when.
Here's the scary part.
Hackers can steal your locked data today.
They can't read it. So they keep it.
Like stealing a locked safe now, and cracking it years later.
So Q-Day isn't just a future problem. It's a today problem.
That's why Google plans to switch its own locks by 2029.
In plain words
Q-Day is the day a quantum computer can break the public-key encryption that protects messages, banking and online payments. No quantum computer can do it today, and nobody knows when it will happen.
- What Q-Day means: breaking RSA and elliptic-curve encryption, the locks used to set up connections and sign things (long-key AES is not broken)
- Why it is a today problem: "store now, decrypt later", where attackers copy encrypted data now and decrypt it once a quantum computer can
- When: experts disagree; a 2025 survey of 26 experts put it at a 28-49% chance within 10 years
- What companies are doing: Google plans to move its own products to post-quantum cryptography by 2029
Sources are in the pinned comment.
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