Post-quantum specialist firms
Firms whose primary business is post-quantum cryptography, described in their own words and linked to their own sites.
What is in this index
Included: firms whose primary business is post-quantum work. Excluded: general security and Big Four practices with a post-quantum offering among many, because a list that includes everyone tells a reader nothing. quantakrypto is not listed here: we publish this directory, so listing ourselves in it would be marketing wearing a directory's clothes.
Reading the labels
“Post-quantum” is used to mean several different things. These labels record which one a firm’s own site describes. They are descriptive, they are not ranked, and none of them means better or worse. A firm carries a label only where its own site supports it, so no label means we did not find it stated, not that the opposite is true.
- NIST-standardised algorithms
- The site names one or more of the algorithms NIST has standardised, such as ML-KEM, ML-DSA or SLH-DSA, or the FIPS numbers that specify them.
- NIST candidate, not a standard
- The site names an algorithm that entered NIST's selection process but has not been published as a finalised standard.
- Scheme of its own
- The offering includes a cryptographic scheme the firm developed itself rather than one published as a standard. This is a statement about what is being sold, not about whether it works.
- Algorithm not named
- The site makes a post-quantum claim without naming the algorithm or family behind it, so a reader cannot tell from the site which cryptography they would be running.
- Quantum key distribution
- The offering involves QKD, which distributes keys using physical hardware. It is a different approach from post-quantum cryptography, which is software running on the machines you already have.
| Name | What it is | Approach and detail | Why | Sources |
|---|---|---|---|---|
| Arqit | A firm selling symmetric key agreement and post-quantum migration tooling, in its own description. | Scheme of its ownkey agreementmigration tooling | Why this is listed Arqit Its three published lines are all quantum security products, which is what this category tests, separately from how the scheme underneath them relates to the published standards. | 2 sources Sep 4, 2026 |
| CryptoNext Security | A firm selling post-quantum migration and crypto-agility software, described in its own words. | NIST-standardised algorithmssoftwarediscoverySDK | Why this is listed CryptoNext Security All four listed products are post-quantum evaluation, discovery, remediation and agility tools, which is a catalogue with nothing else in it. | 2 sources Sep 4, 2026 |
| evolutionQ | A cybersecurity firm working on cryptographic resilience for the post-quantum transition, in its own description. | Quantum key distributionkey managementadvisory | Why this is listed evolutionQ Its two products and its three services are all framed as post-quantum transition work, so nothing in the published catalogue sits outside the scope of this category. | 2 sources Sep 4, 2026 |
| ISARA Corporation | A quantum-safe security firm offering cryptographic solutions for enterprises and product teams, in its own description. | NIST-standardised algorithmsenterprisedeveloper tooling | Why this is listed ISARA Corporation It states quantum-safe security as what it provides, and the two products it names are the whole catalogue, so this is not a broad practice with a post-quantum line attached. | 1 source Sep 4, 2026 |
| Post-Quantum | A quantum-safe security firm whose listed products cover identity, VPN and messaging. | NIST candidate, not a standardidentityVPNmessaging | Why this is listed Post-Quantum It has worked on quantum-safe security since 2009 and all three of its listed products are quantum-safe, so post-quantum is the business and not a line within a larger one. | 2 sources Sep 4, 2026 |
| PQSecure Technologies | A firm supplying post-quantum cryptographic hardware IP and software libraries, in its own description. | NIST-standardised algorithmshardware IPCRust | Why this is listed PQSecure Technologies Every line it lists, from the hardware IP cores to the Rust library, is described as post-quantum or quantum-safe, so the firm is a specialist rather than a general silicon practice. | 1 source Sep 4, 2026 |
| PQShield | A post-quantum cryptography firm shipping hardware and software implementations, in its own description of its work. | NIST-standardised algorithmshardwaresoftware libraries | Why this is listed PQShield Every product line it publishes, the software libraries, the hardware platforms and the accelerators, is post-quantum, so this is the business rather than one offering among many. | 2 sources Sep 4, 2026 |
| Quantropi | A firm whose QiSpace platform bundles a post-quantum public-key scheme, symmetric encryption and entropy delivery. | Scheme of its ownAlgorithm not namedplatformentropysymmetric encryption | Why this is listed Quantropi The QiSpace platform is the whole catalogue and each of its three components is a quantum-secure product, which qualifies the firm whatever algorithm MASQ turns out to rest on. | 1 source Sep 4, 2026 |
| Quantum XChange | A firm selling network-layer quantum-safe key delivery, with Phio TX as its named product. | NIST-standardised algorithmsQuantum key distributionnetworkkey delivery | Why this is listed Quantum XChange Its stated business is upgrading existing networks to quantum-safe encryption, delivered through one named product, so there is no broader practice for that work to sit inside. | 2 sources Sep 4, 2026 |
| QuSecure | A post-quantum cybersecurity firm whose product is a software platform for discovery, remediation and reporting. | NIST-standardised algorithmssoftware platformdiscoverycrypto-agility | Why this is listed QuSecure The single platform it names is a post-quantum one, divided into three modules, so post-quantum is the product rather than an addition to a wider security catalogue. | 1 source Sep 4, 2026 |
Every outbound link here is the subject’s own, and carries nofollow. Listing is not endorsement.