Y Combinator Summer 2021 (S21) Companies

BoldVoice provides AI-powered coaching and feedback to help non-native English speakers improve communication clarity and confidence. The platform serves immigrants and non-native speakers seeking to reduce accent-related barriers in professional and personal contexts.

5 investors

Bolster provides construction management software for residential construction, focusing on estimation and digital workflows to modernize how projects are bought, sold, and managed.

2 investors

Breadcrumbs provides a no-code platform that scores customer and prospect data to surface upsell and cross-sell opportunities for sales teams, requiring minimal setup time compared to traditional analytics solutions.

1 investor

Bree provides overdraft protection of up to $750 with no interest or fees for Canadian consumers living paycheck to paycheck. The service offers early access to earned cash to help cover unexpected expenses and bills.

1 investor

Brite provides a platform for benefits professionals to create and scale benefits education and communication to employees. The software modernizes how companies deliver benefits information during open enrollment.

2 investors

Buoyant Aero provides fully electric, self-flying aerial advertising platforms (blimps) as a service for brands and events. The company handles all aspects from envelope design and custom graphics to flight operations and audience engagement, targeting marketing teams and event organizers.

2 investors

Buró de Ingresos is a verified income and employment data platform for financial institutions in Mexico, providing API access to real-time income verification for consumers and businesses. It serves credit-originating institutions offering consumer loans, credit cards, auto financing, BNPL, and fintech lending.

1 investor

Buzzle analyzes recorded sales and customer success calls to extract trends and metrics that inform product marketing, competitive positioning, and feature demand assessment. The platform automatically identifies customer pain points and market signals from a company's call library.

2 investors

ByteKitchen builds operational software for restaurants to improve profitability through features like food ordering suggestions and digital recipe management.

2 investors

Bytebot is an open-source AI desktop agent that operates in a containerized Linux environment to complete computer tasks via screen interaction, mouse, and keyboard—automating workflows across multiple applications and websites at scale. It serves enterprises and teams needing to automate repetitive work such as data entry, document processing, and multi-system workflows without coding.

2 investors

Cabal provides AI-powered relationship intelligence that infers connections from public data for venture capital platform teams, deal sourcing professionals, and sales organizations. The product delivers connection insights through multiple interfaces including in-app chat, AI assistants, Slack integration, and API access.

3 investors

Cache operates automated warehouses that fulfill convenience item orders placed through delivery platforms, supplying goods to drivers for last-mile delivery to customers.

1 investor

Café is a platform that enables hybrid teams to discover, create, and connect with communities at work based on location, interests, and schedule. The company helps organizations foster employee engagement and fulfillment through intentional relationship-building.

1 investor

Caire Health develops AI software that analyzes medical imaging to assist emergency department teams in rapidly identifying critical conditions and triaging patients for immediate treatment.

1 investor

Canopi provides an API that helps organizations quantify and reduce their carbon emissions.

1 investor

Carbonfact is an environmental intelligence platform that helps apparel and footwear brands and their suppliers measure, understand, and reduce carbon emissions. The platform consolidates supply-chain data and provides scenario modeling and eco-design tools to support emissions reduction across the fashion industry.

1 investor

Careerist helps job seekers discover tech careers that match their personality and interests through a personality quiz matching system.

2 investors

Cartpanda is an e-commerce platform enabling sellers to offer physical and digital products across 150+ countries with a high-converting checkout, multi-currency payment processing, and a unified back office for order and analytics management.

1 investor

Catena develops a conjugation platform for antibody-drug conjugates (ADCs) and multi-payload conjugates used in oncology for solid tumors. The company's technology enables therapeutic structures that deliver dual payloads to cancer targets.

3 investors

CellChorus develops a visual AI platform called TIMING that performs high-throughput dynamic analysis of single cells, measuring cell activation, killing, and movement over time for biopharmaceutical research. The company serves biopharmaceutical companies and therapy developers seeking to understand cellular function and phenotype.

4 investors

Cero operates an automated messaging platform that uses WhatsApp to handle appointment coordination between hospitals and patients across Latin America, handling tasks like confirmation and rescheduling. The service addresses missed medical appointments by enabling patients to confirm or cancel visits without direct phone contact with staff.

2 investors

Charge Robotics automates labor-intensive tasks in solar construction to address deployment bottlenecks as demand for solar energy grows. The company focuses on enabling scalable solar installation through robotics technology.

3 investors

Chari is a fintech app available in Morocco that provides mobile money services including phone recharges, bill payments, peer-to-peer transfers, and Visa card issuance. The platform serves both consumers and merchants, offering wallet functionality, bill payment services, and point-of-sale solutions.

3 investors

Chipax is a financial management software for Chilean companies that automates the collection and organization of financial data including invoices, taxes, and bank transactions, generating reports and dashboards to support financial decision-making. The platform serves small to mid-sized businesses across Chile and integrates with Chilean tax authority systems, banks, and payment gateways.

3 investors