Q-Day

The threat side. Guides to what a cryptographically relevant quantum computer would break, which timeline estimates are worth trusting, and how to tell whether your own Bitcoin addresses sit in the blast radius.

// Guides In This Cluster

Address Reuse: Why It’s Now a Security Flaw, Not Just a Privacy One

It's 2017. You set up one Bitcoin address as your "main one" because you needed somewhere...

BY: Liora Vancek

upd Jul 20, 2026

Bitcoin Quantum Computing Risk: Why Exchange Wallets Are the Weakest Link

Data reveals that 6.04 million Bitcoin (BTC), about 30.2% of circulating supply, sit in wallets with...

BY: Darian Kovel

upd Jul 20, 2026

Grover’s Algorithm vs SHA-256: What’s Actually at Risk

Lov Grover introduced his quantum search algorithm in 1996, two years after Peter Shor unveiled his...

BY: Kaelin Morozzi

upd Jul 20, 2026

Harvest Now, Decrypt Later: How It Affects Crypto Specifically

Harvest now, decrypt later (HNDL) is a class of attack where adversaries capture encrypted data today...

BY: Kaelin Morozzi

upd Jul 20, 2026

How to Check if Your Bitcoin Address Has an Exposed Public Key

Most Bitcoiners audit their addresses for quantum exposure by reading explainers about Shor's algorithm. That's the...

BY: Elias Rennik

upd Jul 20, 2026

Multisig, MPC, and Threshold Signatures: Do They Survive Q-Day?

Here's the question people actually mean when they ask this one: "I moved my coins into...

BY: Elias Rennik

upd Jul 20, 2026

Q-Day: Every Major Timeline Prediction, Compared

The date when quantum computers crack modern encryption has a name. Q-Day. Depending on who you...

BY: Sead Fadilpašić

upd Jul 20, 2026

Shor’s Algorithm Explained Without the Math

RSA encryption runs most of the internet. Every padlock in a browser, every bank login you've...

BY: Sead Fadilpašić

upd Jul 20, 2026

The “9-Minute Attack” Paper: What It Really Says

Google's quantum team did not break Bitcoin. It published a 57-page resource estimate, released on March...

BY: Kaelin Morozzi

upd Jul 20, 2026

What is Q-Day?

One day, quantum computers will become powerful enough to break the elliptic curve cryptography that protects...

BY: Sead Fadilpašić

upd Jul 20, 2026

Which Bitcoin Addresses Are Quantum-Vulnerable?

Bitcoin uses ECDSA, and since Taproot activated in 2021, also Schnorr signatures. Both fall to Shor's...

BY: Kaelin Morozzi

upd Jul 20, 2026

Why Qubit Count Headlines Are Misleading (Logical vs Physical Qubits)

Every few months a headline announces a new milestone in quantum computing. IBM and Atom Computing...

BY: Kaelin Morozzi

upd Jul 20, 2026

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// Guides In This Cluster

Address Reuse: Why It’s Now a Security Flaw, Not Just a Privacy One

Bitcoin Quantum Computing Risk: Why Exchange Wallets Are the Weakest Link

Grover’s Algorithm vs SHA-256: What’s Actually at Risk

Harvest Now, Decrypt Later: How It Affects Crypto Specifically

How to Check if Your Bitcoin Address Has an Exposed Public Key

Multisig, MPC, and Threshold Signatures: Do They Survive Q-Day?

Q-Day: Every Major Timeline Prediction, Compared

Shor’s Algorithm Explained Without the Math

The “9-Minute Attack” Paper: What It Really Says

What is Q-Day?

Which Bitcoin Addresses Are Quantum-Vulnerable?

Why Qubit Count Headlines Are Misleading (Logical vs Physical Qubits)

Menu

Search

Q-Day

// Guides In This Cluster

Address Reuse: Why It&#8217;s Now a Security Flaw, Not Just a Privacy One

Bitcoin Quantum Computing Risk: Why Exchange Wallets Are the Weakest Link

Grover’s Algorithm vs SHA-256: What’s Actually at Risk

Harvest Now, Decrypt Later: How It Affects Crypto Specifically

How to Check if Your Bitcoin Address Has an Exposed Public Key

Multisig, MPC, and Threshold Signatures: Do They Survive Q-Day?

Q-Day: Every Major Timeline Prediction, Compared

Shor’s Algorithm Explained Without the Math

The &#8220;9-Minute Attack&#8221; Paper: What It Really Says

What is Q-Day?

Which Bitcoin Addresses Are Quantum-Vulnerable?

Why Qubit Count Headlines Are Misleading (Logical vs Physical Qubits)

Address Reuse: Why It’s Now a Security Flaw, Not Just a Privacy One

The “9-Minute Attack” Paper: What It Really Says