Quantum Computers Just Got Much Closer to Breaking Your Passwords

On October 21, 2025, IonQ announced a significant achievement in quantum computing. They demonstrated their quantum computer can perform operations with 99.99% accuracy, which doesn't sound like much improvement over 99.9%, but it makes an enormous difference.

What is a Qubit?

Before diving into IonQ's achievement, you need to understand qubits (quantum bits). A regular computer bit is like a light switch: it's either off (0) or on (1). A qubit is fundamentally different.

A qubit can be 0, 1, or both simultaneously until you measure it. This property is called superposition. Think of a coin spinning in the air: it's neither heads nor tails until it lands. While spinning, it exists in both states at once.

Here's a practical example: If you have 3 regular bits, they can represent one number at a time (000, 001, 010, 011, 100, 101, 110, or 111). But 3 qubits can represent all eight of those numbers simultaneously. With 20 qubits, you can work with over a million values (2²⁰) at once. With 300 qubits, you could simultaneously process more values than there are atoms in the universe (2³⁰⁰).

This is why quantum computers can potentially break encryption: they can test millions of password combinations simultaneously instead of one at a time.

The qubits IonQ is talking about are made from trapped ions (charged atoms held in place by electromagnetic fields). When IonQ ran the basic two-qubit operation that creates entanglement and got it right more than 99.99% of the time, they were manipulating these trapped ions to perform calculations.

What Happened

Think of quantum computers as extremely precise machines that need to perform millions of calculations without making mistakes. IonQ's team ran the basic two-qubit operation that creates entanglement and got it right more than 99.99% of the time.

The bigger surprise: they did this without using the usual slow cooling process. Quantum computers typically need to be cooled to near absolute zero and kept incredibly still. IonQ deliberately heated the ions' motion and kept errors at or below 0.0005 per gate.This is like a high-wire artist performing perfectly even in windy conditions.

Why This Matters

Here's where the math gets interesting. If you need to run 1,000 operations:

·       At 99% accuracy, you'll get a completely error-free result about once in 23,000 tries

·       At 99.9% accuracy, you succeed about 37% of the time

·       At 99.99% accuracy, you succeed about 90% of the time

At 99.99% per gate, 1,000-gate circuits succeed error-free about 90.5% of the time. That extra decimal point transforms quantum computers from research toys into potentially useful tools.

The Speed Bonus

Because IonQ skipped the slow cooling step, their quantum computer runs much faster. Transport and cooling can dominate 98-99% of circuit time in these machines. Removing that bottleneck could make quantum computers 10 to 100 times faster at solving real problems.

What This Means for Encryption

Today's internet security relies on mathematical problems that regular computers can't solve in reasonable time. Quantum computers, once large enough, could break these codes.

Experts call this moment Q-Day: when quantum computers become powerful enough to crack today's encryption. For years, people assumed this was 15-20 years away. Recent estimates have shortened that to the early 2030s. IonQ's breakthrough suggests it could happen even sooner.

In May 2025, Craig Gidney at AI Google Quantum AI argued that less than 1 million noisy physical qubits could factor RSA-2048 in under a week. RSA-2048 is the encryption standard protecting most secure websites, banking transactions, and confidential communications.

IonQ's new accuracy level is 10 times better than what those estimates assumed. Better accuracy means you need fewer components to build a code-breaking quantum computer.

Timeline Estimates

Using conservative projections:

·       If quantum computing improves at 2.3 times per year (a reasonable middle estimate), we could see encryption-breaking quantum computers around 2029

·       If progress is slower (2 times per year), it pushes to 2033-2034

·       If companies like IonQ hit their aggressive goals (2.5 times per year improvement), it could arrive as early as 2027-2028

IonQ says they'll demonstrate a 256-qubit system in 2026 and aim for millions of qubits by 2030.

What Organizations Should Do

You don't need to understand quantum physics to act on this news. Here's what matters:

Right Now (next 3 months):

1.    Create an inventory of where your organization uses encryption. This includes websites, VPNs, email systems, and file storage.

2.    Update purchasing requirements to specify "quantum-resistant" or "post-quantum" encryption for new systems. The U.S. government has already published approved algorithms (FIPS 203 and 204).

3.    Start small pilot projects. Test the new encryption methods on a few non-critical systems to learn how they work.

4.    Ask your software vendors about their plans for quantum-resistant encryption. Put it in writing that you expect them to support it.

Within a Year:

1.    Build tools that automatically track what encryption you're using across your organization. You can't protect what you can't see.

2.    Re-encrypt long-term sensitive data using quantum-resistant methods. Hackers might steal encrypted data now and decrypt it later when quantum computers arrive (called "harvest now, decrypt later").

3.    Make your systems flexible enough to swap encryption methods quickly. Don't hard-code cryptography into applications.

4.    Get written commitments from critical vendors about when they'll support quantum-resistant encryption.

Why Act Now

Some people might say, "Why worry if this is still years away?" Three reasons:

1.    Large organizations take years to update their security infrastructure. If Q-Day arrives in 2029, you need to start migrating now to finish in time.

2.    Sensitive data stolen today could be decrypted in 5 years. If your data needs to stay confidential beyond 2030, it's already at risk.

3.    Government regulations are coming. U.S. federal agencies must complete their transitions by 2030-2033. Private sector requirements will follow.

The Bottom Line

IonQ's achievement moves quantum computing from "someday" to "soon." They proved that quantum computers can be both more accurate and faster than previously demonstrated. This pulls the Q-Day timeline closer.

You don't need a PhD to respond appropriately. You need a plan, a timeline, and the commitment to execute. Treat this like Y2K: a known deadline requiring systematic preparation. The organizations that start now will be ready. Those that wait may find themselves scrambling when quantum computers arrive ahead of schedule.

The good news: unlike many cybersecurity threats, we know this one is coming, and we have the tools to prepare. The question is whether organizations will act with appropriate urgency.