336 startups in this batch
Launched during the height of the zero-interest-rate policy (ZIRP) era, W21 was a massive cohort defined by the global mandate for digital transformation. YC funded a record 336 companies, betting heavily on remote-first productivity, hard tech infrastructure, and the expansion of the SaaS model into emerging markets like LatAm and SE Asia.
This batch proved that niche operational workflows—from beauty salon management to satellite-based Earth observation—were ready for high-margin software. They validated a massive enterprise willingness to pay for automated financial planning (FinOps) and tools that solved time fragmentation, moving the needle from simple data entry to complex, integrated business intelligence.
Many W21 startups struggled when the macro environment shifted from "growth at all costs" to a "path to profitability" in 2022. The core failure point was often over-engineered coordination tools that required high-touch onboarding and massive headcount to maintain. Builders today must realize that software which requires human effort to manage is a liability; the goal now is autonomous utility.
The FP&A and Productivity categories from W21 are prime for an AI-agent overhaul. While W21 built the "systems of record" to track data, a 2026 builder can create "systems of action" where AI agents don't just visualize budgets or calendars but autonomously execute re-allocations and scheduling based on high-level business goals.
We make satellites to image everywhere on Earth, every 15 minutes
Kid-friendly, at-home volunteer projects in a box, delivered bimonthly
Enabling consumers split the cost of purchases without a credit card
Providing clean, safe, virus free air for homes, buildings and cars
Neurostimulation implant to restore hearing & speech understanding
We teach Filipinos to become remote software engineers globally.
Aviron transforms workouts with game-based exercise machines, making…
No-code browser automation platform enabling web scraping, data extraction, and task automation via Chrome extension.
Scheduling and workforce management SaaS for home healthcare providers
Automated user acquisition & selling on WhatsApp for businesses
The highest-accuracy global weather data from low-cost flat satellites
Provides live, virtual running classes to runners all around the world
The modern, open source, self-hosted AI customer support platform
Mobile app and coaching program that helps employees sleep better
AI-powered visual content creation and editing platform for background removal, object cleanup, image upscaling, and generative image tools.
AI-powered customer service platform with ClaudIA, a GPT-based agent that automates support tickets for startups.
AI-powered code review tool that approves safe pull requests, detects bugs, and integrates with GitHub Actions.
Free Chrome extension that automates writing with AI-powered autocomplete, reducing writing time by 40%.
Embed NL-to-SQL into your product to enable natural language querying of databases.
DoF provides a high quality, affordable higher education alternative.
DreamWorld is a next-gen Minecraft with generative AI building
Make infinite $$$ off of clothes in your closet without selling them
Creating a New Class of Drugs to Address Incurable Autoimmune Diseases
Driverless electric vehicles at a fraction of the cost of a car.
AI-powered Compliance Platform for PCI 4, CCPA, HIPAA, CIPA, 50+ laws
Discover drugs that control how much cells "squeeze" to treat disease
The place where motivated investors and entrepreneurs co-own together.
AI-powered social media manager that automates brainstorming, content creation, editing, scheduling, and management for DTC brands.
Buy Now Pay Later + Cash Advance for Household Essentials
Video publishing and monetization platform for creators and artists
Payments solution for small-scale construction companies.
Wholesale marketplace for independent retailers buy & manage inventory
GreaseBoss verifes industrial machinery is greased correctly
Autonomous street sweeping as a service by retro-fitting vehicles
Personalized rent-to-own real estate financing using technology in SEA
We help US tech companies hire and manage software engineers in LATAM
Turbocharge customer acquisition through exclusive SaaS partnerships
Electricity price forecasts for energy storage, ev charging, etc.
Shifts FinOps left by integrating cloud cost estimation and governance into engineering workflows to proactively prevent cost issues.
We provide a curated, evidence- based answer to any clinical question.
Juicy marbles makes thick juicy and marbled plant based steaks.
Open source mobile marketing platform. Alternative to appcues /…
Maker of consumer crypto apps: Launchcaster, Frameboard, Maindrop
Record video in a photorealistic virtual studio all from your browser
Clinical skincare tested on diverse skin, now available in Sephora.
ModernLoop helps teams automate and streamline recruiting operations
Buy and grow profitable e-commerce companies selling on Amazon and DTC
Payroll app to pay workers daily for retailers & manufacturers in SEA
Radically reducing capital costs and build time for direct air capture
DIY renovations in a box. Materials, tools, and instructions delivered
The network where sales teams connect to share customer introductions.
The online language school for Latam, with groups led by an instructor
AI-powered SaaS corporate training platform for faster, smarter workforce learning.
Open source continuous profiling software to debug performance issues
Analyzing EHR and messaging data to predict disease before it occurs.
Tools & infra to build and scale high-quality blockchain applications.
User data verification across Employment, Academic Creds, Retail…
Redcliffe Labs is India's Largest Omni-channel Diagnostics platform
All-electric seagliders for fast, affordable regional transportation
Robots that automate the everyday tasks of microbiologists.
LinkedIn content & strategy for founders to get 1M monthly impressions
AI-powered sales development platform that automates prospect research, personalized outreach, and meeting booking for B2B sales teams.
Add powerful decision-making capabilities to any automated workflow.
Build better computer vision models by building better datasets
Debt as a service for companies to lend money to their users at scale.
Chrome extension that records clicks and keystrokes to create no-code automations for repetitive web tasks.
Seamless mobility to, through, and from space. It starts with 100%…
Chrome extension and apps that enable customizable snippets, dynamic templates, and slash commands to eliminate repetitive typing anywhere on the web.
AI-powered platform that enables home service professionals to build SEO-optimized websites, automate customer communications, and manage their entire business operations.
Bioengineered kidneys for patients with kidney failure
AI-led market research interviews, no scheduling, instant insights.
Discovering bispecific antibody drug-conjugates (BsADC) against cancer
AI recruiter that runs outbound sourcing campaigns to find top talent