Y Combinator Summer 2026 (S26) Companies

Poth Labs builds an AI-powered survey platform that uses adaptive questioning and knowledge graphs to convert employee feedback, customer surveys, and market research into statistically validated insights. The platform serves organizations seeking deeper understanding from survey data through automated analysis that replaces manual interpretation.

2 investors

Praxis AI collects egocentric video, 3D scans, and multimodal sensor data from industrial and residential work environments through partnerships with large corporations, then sells this real-world training data to AI companies developing physical robotics and other systems.

2 investors

Prescience is a financial technology platform providing health benefits administration, care navigation, and HSA management services for employers and their members.

1 investor

Princeps is developing financial infrastructure for the compute economy, including instruments such as compute reserves, compute bonds, SLA guaranties, and a clearing house tied to GPU/compute capacity. The company positions itself around underwriting and financial products for AI-era compute resources.

1 investor

Prized is a low-code platform that enables non-engineers to build internal tools by describing them in plain language; the platform connects to existing enterprise systems with admin-approved connectors and maintains role-based access control and audit logging.

2 investors

Prodigy Research is an AI research lab building a foundation model for quantitative trading, and operates live trading systems in financial markets. It targets the trading and financial-reasoning domain, applying proprietary AI models and agents to equities and delta-neutral strategies.

3 investors

Proprio Robotics develops robots that perform physical maintenance tasks inside data centers, such as fan insertion, cable switching, RAM extraction, GPU cabling, disk hot-swapping, and heatsink removal. The company aims to enable autonomous data center operations.

3 investors

ProvenMetal manufactures printed circuit boards with fast seven-day turnaround and 100% X-ray inspection coverage. The company serves hardware manufacturers requiring rapid prototyping and assembly with domestic US-based production.

2 investors

Radley is an AI-native radiology group that reads imaging studies for hospitals and imaging centers, using AI to draft reports that its radiologists review, correct, and sign in the client's format. It provides flexible coverage for volume spikes, nights, and unfilled positions, and handles delivery to ordering providers, critical-finding notifications, and follow-up tracking.

2 investors

Rapidfolio automates manual processes for the financial industry using AI. The company was founded by the team behind Sable, a fintech that provided credit products to underbanked Americans.

2 investors

Rasyn.ai offers Marigold, an AI research assistant that lets scientists ask research questions, run tools, or delegate entire tasks, returning results such as structures, charts, code, and papers in panels. It provides 54 runnable tools, 40 executing on connected hardware and 14 on hosted endpoints.

1 investor

Rational provides AI agents that automate recurring accounts payable, close coordination, reconciliation, and document management tasks for finance teams, while keeping approvals and final decisions with human staff.

2 investors

RealPact provides voice-powered AI agents for real estate brokerages that automatically retrieve deed, property, and tax records, draft contracts, and move transactions from hours to minutes. The platform functions as an AI-native operating system handling operational work in real estate deals.

1 investor

Rekursiv.ai builds autonomous systems of AI models that act as "AI Scientists," forming hypotheses, designing and running experiments, and discovering new knowledge such as novel machine learning algorithms. The company targets research and AI development, aiming to scale automated scientific discovery.

2 investors

Rex is an agentic finance platform that connects to existing enterprise financial systems and automates manual operational finance work like collections, reconciliation, and portal uploads using AI agents. The product is designed for finance teams at scaled technology companies seeking to delegate repetitive tasks while maintaining governance and audit compliance.

3 investors

Riften provides a routing layer that sits between a company's applications and large language model APIs, directing each request to the least expensive capable model and using self-hosted open-weight models where possible to reduce inference costs. It also uses the resulting task data to train private, company-owned models on recurring work, serving businesses that run AI-powered applications.

2 investors

Rindler provides a platform that enables AI agents to reliably navigate and interact with any website, offering infrastructure for deterministic web access. The platform serves developers and organizations building AI agents that need to automate work across web-based systems.

1 investor

Rise Reforming converts stranded biogas from wastewater plants, farms, and landfills into valuable chemicals including dimethyl ether (DME), methanol, and dimethyl carbonate (DMC) using modular, containerized technology. The company serves the chemical industry, offering a low-carbon alternative to fossil fuel-dependent chemical production with domestic feedstock security.

2 investors

Risklytics simulates natural disaster risks (wildfire, flood, wind, earthquake, debris flow) on individual residential properties using digital twins built from building data and satellite imagery. The platform provides risk scores, modeled annual losses, and retrofit recommendations for homeowners.

1 investor

Robocurve develops open-source tools and benchmarks for evaluating the real-world capabilities of AI systems and robots. The company serves robotics labs and the broader public by providing independent, rigorous evaluation frameworks to assess progress in physical AI and general-purpose robotics.

2 investors

RonanRx offers personalized GLP-1 weight-management care delivered via text, where a licensed physician reviews a patient's history to set an individualized dose, titration schedule, and patient-specific adjunct, and a licensed pharmacist at the patient's selected pharmacy verifies and releases compounded, patient-specific prescriptions. It serves individual patients in the US (availability varies by state) and plans to add hormone therapy (HRT).

3 investors

Salem Robotics develops autonomy software for robotic radiological surveys and inspections in nuclear and hazardous environments. The platform automates route planning, radiation measurement collection, and compliance reporting on existing robot hardware to reduce worker exposure and improve data consistency.

3 investors

Screenpipe is a local-first context layer that captures screen activity for enterprise AI agents, enabling them to act on real user behavior. The platform serves enterprise organizations building or deploying AI agents.

3 investors

Shepherd is an AI assistant that integrates with a team's existing tools (messaging, code editors, CRM platforms) to create a unified memory system. It automatically captures messages, calls, and commits, allowing teams and AI agents to query and act on company information without manual tagging.

1 investor