Learn
Will your data outlive the encryption around it?
Encrypted traffic can be recorded today and kept. If a quantum computer able to break today’s public-key cryptography is ever built, that recording can be decrypted then, even though it was protected when it was sent. Whether this matters to you depends on one number: how long the data has to stay secret. Enter it below and see how that period lines up with the date the standards body stops allowing today’s key exchange.
What protects it in transit?
What protects it at rest?
Result
Data you send this year must stay secret until 2036.
In transit. Today’s key exchange is scheduled to be disallowed after 2035, so recorded traffic is not covered for the whole period.
At rest. You do not know what protects it at rest, so treat it as public-key encrypted until you find out. Stored data wrapped in RSA or elliptic-curve keys depends on cryptography that is disallowed after 2035, before this period ends.
What to do next
- Enable hybrid ML-KEM key exchange on your servers. How to enable post-quantum key exchange
- Check whether any domain already negotiates it. The scan is free and runs from outside. Check a domain
- For a whole estate, Fleet Watch rescans your domains and suppliers every week. See Fleet Watch
Dates come from NIST IR 8547 (initial public draft): quantum-vulnerable public-key algorithms are deprecated after 2030 and disallowed after 2035. This page does not predict when a quantum computer will exist.
What this calculator uses, and what it does not
The result rests on one published schedule. NIST IR 8547 (initial public draft, November 2024) lists the public-key algorithms that a quantum computer could break, including RSA, ECDSA and ECDH, as deprecated after 2030 and disallowed after 2035. The same document does not treat symmetric encryption such as AES-256 as broken by quantum computers.
The calculator does not predict when a quantum computer will exist. Nobody can give that date with confidence, and this page does not try. It uses 2035 only because that is the year after which the standards body no longer permits the cryptography most servers use for key exchange today. If your data must stay secret beyond that year and it travels under that cryptography, the recording problem applies to it.
The transit question is about key exchange, the step where two systems agree on a secret before the connection is encrypted. That is the part a recording exposes. Post-quantum key exchange, in practice hybrid ML-KEM, closes it for everything sent after it is enabled. It does not help with traffic that was already recorded.
Related
Sources
Every claim links to the original document, never to a news outlet or an aggregator.