Bio

Carina Hong (Letong Hong) is a Chinese-American mathematician and entrepreneur, born June 8, 2001 in Guangzhou, China. She is the founder and chief executive officer of Axiom Math, the Palo Alto formal-mathematics AI company she established in 2025 to build machine-checkable mathematical reasoning in the Lean programming language. As of May 2026, she leads Axiom Math following the December 2025 perfect score on the William Lowell Putnam Competition by the company's AxiomProver system, the December 2025 automated proof of a 20-year-old open number-theory conjecture, and the March 2026 Series A of $200 million at a $1.6 billion post-money valuation led by Menlo Ventures.

At a glance

• Education: Dual bachelor's degrees in mathematics and physics, Massachusetts Institute of Technology (completed in three years, 2018 to 2021); Rhodes Scholar at the University of Oxford (2021 to 2023), with a master's in neuroscience; Knight-Hennessy Scholar in the JD/PhD program at Stanford University before leaving in her first year to found Axiom Math.
• Current role: Founder and Chief Executive Officer of Axiom Math since 2025.
• Key contributions: founder of Axiom Math; nine peer-reviewed mathematics publications spanning number theory, combinatorics, theoretical computer science, and probability; AxiomProver perfect 12 of 12 result on the December 2025 Putnam Competition; AxiomProver autonomous proof of a 20-year-old open number-theory conjecture in December 2025.
• Awards: 2023 AMS-MAA-SIAM Frank and Brennie Morgan Prize for Outstanding Research in Mathematics by an Undergraduate Student; 2022 Alice T. Schafer Prize from the Association for Women in Mathematics; 2022 Stanford Maryam Mirzakhani Fellowship; 2021 Rhodes Scholarship.
• LinkedIn: Carina Hong

Origins

Hong was born June 8, 2001 in Guangzhou, China, and grew up there as a first-generation college student. She joined a free Olympiad mathematics program early and was one of the few female members of her provincial Mathematics Olympiad team in high school, with distinction in national competitions. Before college, she participated in the Ross Mathematics Program at Ohio State and the Stanford University Mathematics Camp.

She entered MIT in 2018 to read mathematics and physics, completing dual bachelor's degrees in three years. She published nine peer-reviewed papers as an undergraduate spanning number theory, combinatorics, theoretical computer science, and probability, with research conducted at Budapest Semesters in Mathematics, the University of Minnesota Duluth REU, and the University of Virginia REU. The undergraduate research record produced the 2022 Schafer Prize and the 2023 Morgan Prize, the latter being the highest honor in the United States for undergraduate mathematical research.

She was elected a Rhodes Scholar in 2021 to study neuroscience at Oxford, deferring an offer of admission at Stanford's mathematics PhD program. After Oxford, she entered Stanford's combined JD/PhD program in mathematics on a Knight-Hennessy Scholarship before leaving the program in her first year to found Axiom Math.

Career

Hong founded Axiom Math in 2025 in Palo Alto, with a research thesis that formal mathematics in the Lean programming language could solve the verification problem that limits the trustworthiness of language-model mathematical output. The founding capital structure included a 2024 seed round of $64 million at a $300 million valuation led by B Capital, with Greycroft, Madrona, and Menlo Ventures participating. The seed-round size and pre-product valuation were unusual for a research-stage AI company and reflected the strategic interest in formal-mathematics-AI as a category and the founder's research credibility.

In December 2025 two events brought Axiom Math into wider visibility. AxiomProver, the company's formal-mathematics AI system, solved all 12 problems on the William Lowell Putnam Mathematical Competition with formally-verified Lean proofs. The Putnam is the principal undergraduate-mathematics competition in North America; out of more than 150,000 attempted exams in 98 years, only five human contestants have produced perfect 120-of-120 scores. The same AxiomProver system also produced an autonomous proof of a 20-year-old open number-theory conjecture that Ken Ono, a senior number-theorist and Hong's longtime mathematical-research collaborator, had been unable to solve himself. Ono joined Axiom Math as Founding Mathematician in December 2025.

The March 2026 Series A of $200 million at a $1.6 billion post-money valuation, led by Menlo Ventures, completed Axiom Math's first full year out of stealth and crossed the unicorn threshold. The valuation jump from the $300 million seed to the $1.6 billion Series A reflected the AxiomProver Putnam result, the Ono conjecture, and the broader strategic interest in mathematical-superintelligence-class AI systems. Axiom Math's positioning sits within the formal-mathematics-AI insurgent cohort alongside Harmonic, with Hong's emphasis on the Lean substrate and AxiomProver's verification-first approach distinguishing the company from peers including the language-model-style approaches at frontier labs.

Notable contributions

• Undergraduate mathematical research (2018 to 2021). Nine peer-reviewed papers spanning number theory, combinatorics, theoretical computer science, and probability, conducted across the Budapest, Minnesota Duluth, and Virginia research programs.
• 2022 Schafer Prize from the Association for Women in Mathematics, for excellence in undergraduate mathematical research.
• 2023 Morgan Prize from the AMS, MAA, and SIAM, the highest United States honor for undergraduate research in mathematics, awarded for her work in number theory and related fields.
• Axiom Math founding (2025). Founded the Palo Alto formal-mathematics AI company with the founding research thesis that machine-checkable proofs in Lean can close the trust gap between language-model mathematical output and rigorous proof.
• AxiomProver Putnam result (December 2025). The AxiomProver system solved 12 of 12 problems on the December 2025 Putnam Competition with formally-verified Lean proofs.
• AxiomProver open-conjecture proof (December 2025). Autonomous proof of a 20-year-old open number-theory conjecture by AxiomProver.

Position in the field

As of May 2026, Hong occupies a distinctive position among 2025-vintage Insurgent-lab chief executives. The combination of an undergraduate research record at the Morgan Prize tier, a Rhodes Scholar credential, an in-house formal-mathematics AI system that has produced unambiguous capability evidence on the Putnam Competition, and a Series A unicorn round at the same firm she founded the prior year is structurally unusual.

The closest peer comparator is Tudor Achim at Harmonic, the other principal mathematical-superintelligence-class AI insurgent of the 2023 to 2026 cohort. Industry coverage has consistently grouped the two companies together while distinguishing Axiom Math's academic-research credibility (Hong's record plus Ono's Founding Mathematician role) from Harmonic's Tenev-and-Sequoia consumer-fintech-leadership-adjacent investor profile. The capability-disclosure axes also differ: Axiom Math has emphasized the Putnam result and the Ono conjecture, while Harmonic has emphasized the 2025 International Mathematical Olympiad result.

Outlook

Open questions over the next 6 to 18 months:

• AxiomProver capability cadence. Continued benchmark and result disclosures beyond the Putnam and Ono-conjecture results, including any further open-conjecture autonomous proofs.
• Applied verification deployment. The pace and scale of code verification and adjacent high-assurance technical applications, with named customer disclosures as the principal commercial signal.
• Senior research recruiting. Continued hiring against academic formal-mathematics research programs and frontier-lab AI-for-math research teams.
• Series B fundraising. Whether Axiom Math closes a Series B at a step-up valuation in 2026 or 2027, and the strategic-investor configuration.
• Competitive dynamics with Harmonic. Direct technical and commercial competition with Harmonic and the broader peer set as both companies progress through 2026 to 2027.

Sources

• Letong (Carina) Hong biography. HandWiki biographical entry covering education, awards, and research record.
• Carina Hong on Knight-Hennessy Scholars at Stanford. Stanford Knight-Hennessy program biographical entry.
• Schafer Prize 2022. Association for Women in Mathematics award announcement.
• MIT spotlight on Hong's Schafer Prize. MIT Department of Mathematics announcement.
• Carina Hong on the Knight-Hennessy program. Knight-Hennessy biographical detail.
• Superintelligent AI Mathematician: Carina Hong, Axiom. Thought Economics founder interview.
• Madrona: Axiom Math Tackles One of AI's Hardest Problems. Madrona investment-thesis reference.
• Menlo Ventures: AI Will Write All the Code. Mathematics Will Prove It Works. Menlo investment-thesis reference.
• The Standard: Carina Hong's AI startup hits $1.6b valuation. Series A reference.
• Tech Funding News: Axiom Math AI mathematician $64M seed. Seed-round and Series A coverage.
• B Capital: Toward Mathematical Superintelligence. B Capital investment-thesis reference.