The National Institute of Standards and Technology develops post-quantum cryptography standards to protect confidential electronic information against future quantum computers. The agency evaluates new encryption algorithms submitted by global experts and creates technical guidelines. These standards aim to help organizations transition their digital security systems before quantum computing technology matures.
Understanding the quantum threat
Conventional cryptographic algorithms work by multiplying two very large prime numbers to obtain an even larger number, according to the National Institute of Standards and Technology, or NIST. Standard computers find it extremely difficult and time-consuming to reverse this process and figure out which original prime factors were used.
For large enough numbers, a conventional computer might need billions of years to identify these prime factors and break the encryption. However, a sufficiently capable quantum processor could sift through all potential prime factors simultaneously.
By finding the correct answer exponentially faster, a quantum computer could solve this puzzle in days or hours. This capability would completely break many current public-key cryptosystems, putting state secrets, financial statements and personal data at risk.
Evaluating new mathematical approaches
To defend against this capability, NIST evaluates post-quantum encryption algorithms designed to resist cyberattacks from both conventional and quantum computers. These new methods rely on different mathematical foundations, such as structured lattices and hash functions, rather than the factoring of large prime numbers.
Experts expect these specific types of math problems to remain difficult for any computer to solve. NIST standardizes algorithms for two main tasks: general encryption to protect exchanged passwords and data, and digital signatures to authenticate identity.
The agency states that these post-quantum algorithms differ entirely from quantum cryptography. While post-quantum algorithms use mathematical techniques to defend against quantum computers, quantum cryptography fundamentally relies on the physical properties of quantum mechanics to create secure encryption.
Standardizing and testing algorithms
NIST develops these encryption standards through a transparent public process involving international cryptographers, government, industry and academia. The agency solicits proposed algorithms and releases them for open analysis so security experts can attempt to crack them.
Through multiple rounds of evaluation spanning several years, reviewers assess the candidates. They test how the algorithms perform on large computers, smartphones and small devices with limited processor power, such as smart cards and individual microchips.
The agency notes that it treats the standard development process as a thorough analysis rather than a competition. Because candidate cryptosystems have completely different design attributes and mathematical foundations, direct comparisons between algorithms are often impossible.
Managing the transition timeline
NIST issues technical road maps detailing how organizations should transition away from quantum-vulnerable algorithms. According to NIST documentation updated in 2026, federal mandates establish a primary target of 2035 for completing migration across government systems.
Under accelerated federal deadlines, systems with high impacts and assets of high value must update their key establishment by 2030. Their digital signatures must transition by 2031. NIST accommodates a hybrid approach during this transition, allowing organizations to combine conventional algorithms with post-quantum cryptography for increased security.
The agency emphasizes that migration must occur well before large-scale quantum computers are built. Early transition is necessary to counter the threat of adversaries capturing encrypted data immediately with the intention of decrypting it years later when the technology exists.