# Quantum breaks Bitcoin by ___

> December 31, 2027 leads at 23%, runner-up 5% across 2 winner-take-all outcomes — refreshed just now.

URL: https://simplefunctions.dev/odds/quantum-breaks-bitcoin
Updated: 2026-05-09T04:20:39.550Z
Category: crypto · Topic: bitcoin
Status: active

## Headline

- Leader: December 31, 2027 at 23%
- Runner-up: December 31, 2026 at 5%
- Outcomes: 2 (winner-take-all)
- Venue: Polymarket (2 contracts)
- 24h volume: $29

## Bound contracts (2)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| December 31, 2027 | 23¢ | +1pp | $7 | polymarket | /markets/quantum-breaks-bitcoin-by-december-31-2027-polymarket-0x05aa263619fad5bfd26d4fd2840ea5173ba8397315d1d7a1dc5979c6d136dedc |
| December 31, 2026 | 5¢ | ±0 | $22 | polymarket | /markets/quantum-breaks-bitcoin-by-december-31-2026-polymarket-0x11921d4ea572e1f804a719ced0d5700676461f75d4394205ad6620f408138d0f |

## 30-day trajectory

| Day | December 31, 2027 | December 31, 2026 |
|---|---|---|
| 2026-05-01 | 20 | 8 |
| 2026-05-02 | 19 | 8 |
| 2026-05-06 | 21 | 8 |
| 2026-05-07 | 21 | 5 |
| 2026-05-08 | 22 | 5 |

_6 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## What moved the line

- 2026-05-07 · December 31, 2026 −3pp 8→5¢ · polymarket

## Analysis

This 19% probability estimates the odds that quantum computing developments will compromise Bitcoin's security by some point in 2026. The estimate reflects assessments of both near-term quantum advancement timelines and Bitcoin's cryptographic vulnerabilities. The probability would rise if major quantum computing breakthroughs occur, particularly achievements in error correction or qubit count that bring practical cryptanalysis closer to feasibility. It would fall if quantum progress stalls relative to current expectations or if Bitcoin implements post-quantum cryptography upgrades preemptively. Key catalysts include major announcements from quantum computing firms, research publications demonstrating advances in relevant attack methods, and any significant Bitcoin protocol updates addressing quantum risks. Current market pricing suggests participants view large-scale quantum threats as possible but not imminent within this timeframe.

### Key factors

- Current quantum computers lack sufficient qubits and error correction to threaten Bitcoin's ECDSA encryption, with estimates suggesting 1-2 million logical qubits would be required for a cryptographically relevant attack
- Bitcoin's development roadmap includes no scheduled post-quantum cryptography migration by end-2026, leaving protocol changes as a major uncertainty factor
- Major quantum hardware companies have not announced near-term milestones suggesting cryptographically relevant quantum computing within six months
- The timeline assumption matters: quantum breakthroughs that threaten Bitcoin could occur years away, making 2026 a narrow resolution window for this specific question
- Market concentration is low across these contracts, with top volumes under $54k daily, suggesting limited institutional conviction around the exact probability level

## Methodology

Headline is the **leader's price**, not an arithmetic mean — averaging disjoint winner-take-all outcomes is meaningless. Per-outcome prices come from the venue's last-traded mid; cross-venue values are simple means across contracts on each venue.

## How to use this data

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- JSON: https://simplefunctions.dev/api/public/odds?slug=quantum-breaks-bitcoin
- Topic hub: https://simplefunctions.dev/predictions/bitcoin

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