Marketing Startups funded by Y Combinator (YC) in the San Francisco Bay Area 2026

Webflow is the leading no-code visual web development platform. It seamlessly generates sophisticated code so anyone can build powerful web-based businesses and adapt to changes without developers or months of building. From entrepreneurs and creative agencies to Fortune 500 companies, Webflow makes the internet a more inclusive place by making the tools to build on it more accessible to more people, fueling business growth. Webflow powers websites for innovators like Discord, Monday.com, IDEO, Orange Theory Fitness, TED, and Dropbox. Webflow is backed by Y Combinator, Accel, CapitalG, Silversmith, and other awesome investors.

Reframe deploys AI agents to manage overseas hardware manufacturing. Our Agents can understand your build matrix, coordinate waterfall schedules with supplies, and negotiate pricing, ensuring that your parts won't miss the next build.

sitefire helps companies win customers on ChatGPT, Gemini, and other AI agents. We identify the content that drives AI visibility, and recommend actions that work: third-party sites, UGC content, and new blog posts. But we don’t stop there. sitefire synthesizes the top-cited web pages into AI-optimized, ready-to-publish web pages. You just publish and start winning leads.

Bizzy handles your calls, captures and qualifies leads, and books appointments directly into your CRM. It understands your services better than a receptionist would, routes and escalates calls, and syncs with your existing tools to incorporate complex workflows, all so your team can focus on servicing leads, not qualifying them.

Claybird makes studio-quality video ads in under 72 hours for brands like Coca-Cola, Walmart, Eight Sleep, Delve, and Mercor. Claybird’s AI agents use single-image NeRFs, fine-tuned image editing models, and eval layers for picture-perfect, consistent results at scale.

Narrative automates the creation and distribution of high-quality sports highlight videos for broadcasters, teams, and leagues.

Uplane replaces marketing agencies with AI. We generate hundreds of ads with matching landing pages and steer the ad spend across channels like Meta, Google, LinkedIn and others. By connecting to CRM and ERP data, Uplane learns what drives profits and continuously improves campaigns. Companies waste billions on bad ads, mismatched landing pages, and poor budget allocation. Uplane fixes this by replacing a patchwork of agencies, spreadsheets, and siloed tools with one self-improving system. The result: Higher ROAS for enterprises and effortless, expert-level marketing for SMBs.

Bluma is the first AI short form content engine. In a post-AI world, attention is the most valuable commodity. Social media is only growing faster and faster, and we're still early. We automate your entire consumer marketing strategy with content templates, generating on brand videos on autopilot. Everything that a growth team would plan, script, produce, and edit, Bluma automates end-to-end and at scale. We can make entire UGC videos from a reference at 10x the scale and 1/10th of the cost. We remove the operations of hiring, managing, creatives and spend with AI.

Bear helps companies capture and convert the highest-intent leads on the internet - visitors clicking from ChatGPT, Perplexity, and other AI agents. Bear owns the entire funnel from agent discovery to conversion.

Using our 6+ years of influencer marketing experience to help companies run their influencer campaigns at scale. Fully managed solution to drive real, attributable results to their marketing efforts.

Make sure your brand doesn't get left behind by the paradigm shift from traditional search to generative search. AthenaHQ helps your brand get discovered on generative engines like ChatGPT, Perplexity, Claude, Gemini, and more using generative engine optimization (GEO). AI search is expected to overtake traditional search in the next 3 years. We are building AthenaHQ to fill that gap. Team of former product manager on Google Search's information acquisition team, Deepmind Generative Media team, and ChatGPT superusers.

Rankai is building an AI-powered Marketing Agency, starting with search engine marketing.

Unusual helps brands discover and change how AI models talk about them. Unusual surveys models with thousands of targeted probing questions to understand how they form their opinions. We examine the sources they pull from, and find patterns in their reasoning, that let us create content and PR engineered to change those models’ minds. A typical Unusual customer sees more than a 40% increase in traffic from AI models within a month of going live. Beyond driving more traffic, customers have used Unusual to shift models’ perception of their brand from “niche” to “enterprise-platform”, from “scrappy” to “customer-obsessed”, and from “good for startups” to “a solid bet for the middle market”. We work with top companies including Reducto, Monarch Money, and more.

We build AI compliance for external marketing. For example, we work with major creators to ensure that their content meets credit card marketing guidelines.

Stormy: AI-Driven Influencer Marketing Streamline influencer outreach and let your product shine. • Discover: AI pinpoints ideal influencers with 99.8% accuracy. • Outreach: Auto-send personalized emails and follow-ups. • Close: AI negotiates and finalizes deals seamlessly. Focus on building—Stormy handles distribution on autopilot. Founders from YC have discount! Please DM me on twitter: @karmedge or email

We help businesses capture what resonates, make it repeatable, and turn attention into lasting momentum. With Typa, you can build a scalable inbound growth engine with content that compounds. We make this possible through three pillars: 1. A tone of voice that always sounds like you. Typa learns your style, cadence, and perspective so every piece of content reflects your authentic voice. 2. A knowledge base that updates in real time. Your digital clone continuously absorbs everything you say and create, ensuring your content always reflects your latest thinking. 3. A personal ghostwriter that’s always just a call away. Puff is your 24/7 AI ghostwriter and strategist, available via phone or WhatsApp whenever you want to brainstorm, plan, or execute. Currently supported channels: X, LinkedIn, Bluesky, and blog/newsletters.

Gauge helps your company show up in more AI answers. With traffic leaving search, traditional SEO is dying. Our customers are seeing inbound traffic from AI answers double every quarter.

Apten is an omni-channel AI agent that engages and nurtures leads across text, call, email, and webchat. We help enterprises in consumer services convert more leads.

Resonance hyper-personalizes MarTech campaign content and automatically refreshes and stores high performing content for re-use.

Always-on AI agents for 1-1 personalization at scale

Surface Labs helps B2B companies capture, qualify, and convert inbound leads through intelligent contact forms. We replace tools like HubSpot Forms, Zapier, and Chili Piper with a single platform that embeds on any site with one line of code. Our AI agents handle lead capture, enrichment, routing, follow-up, and CRO testing — automating what used to require full marketing ops teams. Customers see a 30% lift in conversions in under 2 weeks, and our partial response capture feature collects 50% more emails from form drop-offs.

Kite is a screen recorder that makes your demo videos look like Apple commercials in minutes. Simply record your app (works for iPhone recordings too!). Kite will track your cursor and keyboard inputs, so it can automatically zoom in on the action with professional 3D animations. Kite is as easy as Canva, but your videos will look like they came out of OpenAI or Figma. - One-click cinematic 3D animations - Display recordings on 3D mockup devices (MacBooks, iPhones etc) - Combine unlimited recordings into one video - Edit, adjust speed and trim recordings - Add text scenes and text annotations alongside recordings - AI voiceovers using state of the art text to speech models - Free music library - Brand kit–upload your logos, colors and fonts - Start from our template library or start from scratch Kite is used by hundreds of YC companies for launch videos, social media posts, landing page demos, changelog updates, feature releases and more.

1stCollab is the first influencer platform that fully automates and optimizes every aspect of your influencer marketing program. We’ve helped hundreds of startups launch their first campaigns and enabled larger brands to scale to thousands of influencers, while saving them over $1M annually in influencer spend. What we offer: - Smart search & recommendations – Instantly connect with thousands of relevant influencers. - Full campaign automation – From outreach and negotiations to contracts, payments, and taxes, we handle it all. - Real-time performance tracking – Monitor conversions, revenue, and run A/B tests with detailed reporting.

Banabo is the first Marketing Attribution OS with the mission of getting a company’s marketing waste to zero. We help companies achieve this goal by mapping a website visitor’s entire journey through a sale, and showcasing the true impact of each touchpoint. Accurate attribution previously wasn’t possible due to GDPR in the EU, CCPA in California, and the iOS 14 Privacy Changes. And with Google banning tracking cookies in 2023, we’ve built the first fully cookieless marketing attribution solution, using zero personal data.

Sprites AI automates customer acquisition for entrepreneurs. Our AI agent handles managing SEO, running paid ad campaigns, content marketing, influencer outreach—tasks that normally require hiring multiple people or agencies. Entrepreneurs using our platform acquire customers much faster and scale their growth funnel without the overhead of building marketing teams or hiring expensive agencies. The result: SMBs and solo founders can now scale revenue like they have a full marketing department. We're arming entrepreneurs and small businesses globally with systematic customer acquisition run by AI- so they can focus on the important things that make their offering unique.

AI-driven push marketing tool for mobile apps, that can be integrated in hours, without any code writing. nGrow connects to behavioral data from analytical systems like Amplitude, Google Firebase, Mixpanel etc. and allows to setup auto push campaigns with an hours. It's as simple as running Google or Facebook but in push notifications channel. nGrow.ai customers usually got their up to 30% incremental Revenue lift. We got Amplitude COO and ex-Google advisors on board

Bobidi runs Upswell, a platform that brings new guests to local restaurants and helps turn them into regulars. We transform restaurants’ promotional videos on social media into engaging quiz campaigns based on the video content. Winners receive cash rewards that can be redeemed at the restaurants.

HOKALI is the marketplace for buying after-school programs and enrichment activities with high-quality, vetted vendors in the US. We simplify the process of booking, organizing, and managing after-school programs and camps for schools.

Writesonic is the GEO (Generative Engine Optimization) platform that tracks your AI visibility across ChatGPT, Gemini, and 10+ AI search platforms. Then helps you take precise actions to boost visibility—create new content, refresh existing pages, or reach out to sites that mention competitors but not you. Track, Act, and Win AI search from one platform. 15,000+ five-star reviews across G2, Trustpilot, and Capterra.

At Sentiyen, we build GPT-based AI assistants that are trained on your content and enable your audience to get the answers they need 24 hours a day. We allow creators and businesses scale themselves to unlimited 1:1 conversations with potential customers, which helps increase revenue, reduce spend, and improve customer satisfaction.

Mailmodo is an email marketing software that helps marketers create app-like experiences in email by adding forms, shopping cart, calendar, NPS and more widgets within the email. Our interactive emails reduce the number of steps for users, thereby increasing email conversions. You can use it to collect feedback from your users, book meetings with prospects, recover abandon carts, generate leads, and more all within emails.

Open source mobile marketing automation and customer onboarding platform. Alternative to braze customer io / iterable / pendo / appcues . Segment and engage your users with complex scheduled push notification, sms and email campaigns.

Hightouch is the leading Composable CDP and AI Decisioning platform allowing marketing teams to activate their data warehouse to build 1:1 customer experiences with data and AI agents.

Start a newsletter. Build your community. Make money from subscriptions. Publishing is free, with no limits. We only make money when you do.

We fix and monitor emails in spam. We monitor automatically where your emails is going, we alert you when it's going in spam and we fix it with you. Best of all, the monitoring is free!

From MIT's App Inventor and YCombinator's W2016 batch, Thunkable allows anyone to build powerful native apps. With Thunkable, it's simple to design, and simple to code-- simply drag and drop to create fast, native, reliable apps. You don't need to download large development suites, command-line kits, or simulators. You can use the many built-in app templates as they are, or make changes. Make your changes online and see them on your device instantly with the Thunkable mobile app. Upload your apps directly to the Play Store or App Store or send them to friends!

Founded in 2015, Apollo.io is a lead intelligence and sales engagement platform trusted by nearly 9,000 paying customers, from rapidly growing startups to some of the largest global enterprises. Our community-based approach to crowdsourcing data gives users maximum coverage while ensuring data accuracy. Our advanced algorithms and unique data acquisition methods help over 500,000 sales professionals enrich and analyze prospects' data to increase quality conversations and opportunities. We have notable investors: Y Combinator and Nexus Venture Partners. We recently completed a Series B financing to fuel our next growth phase. We have reached and maintained profitability for the last 18 months. Our growth and customer feedback set us apart from competitors. Apollo had over one million sign-ups for its platform in the past year, and the number of weekly active users increased by over 400%. We are a top-ranking G2 Crowd vendor in the Sales Intelligence, Lead Intelligence, Marketing Account Intelligence, and Sales Engagement categories. Our highest scores are in the B2B data space for accuracy and ROI based on customer reviews.

Welcome to Netomi AI, where we are revolutionizing the world of customer experiences through cutting-edge artificial intelligence. Our mission is clear: to create AI that not only solves mission-critical problems for the world's largest brands but also fosters genuine customer love. Backed by industry titans like Y-Combinator, Index Ventures, Jeffrey Katzenberg, and Greg Brockman, Netomi AI is at the forefront of defining the future of AI-driven customer engagement. At Netomi, we embody our core values in everything we do: Passion: We love what we do, genuinely. We persevere, creatively problem solve, and grow from adversity. Customer Focus: We obsess over creating a positive impact and deliver experiences that meet or exceed the needs of our customers, and their customers. One Team: We believe in working collaboratively as One Team to meet shared objectives and goals. Joining Netomi AI means being part of a dynamic, fast-growing team that values innovation, creativity, and hard work. As a key player in the Generative AI revolution, you'll have the opportunity to significantly impact our success while developing your skills and career in the ever-evolving field of AI. Netomi AI is not just a workplace; it's a community of visionaries shaping the future of customer engagement. If you're ready to be part of something extraordinary, where your passion aligns with our values and vision, we invite you to explore opportunities with us. Your journey to redefine customer experiences with brand-safe AI starts here. Mission To empower the highest quality customer experiences with brand-safe AI. Vision Building Brand and Customer Love

Revl is an experience technology company and Y Combinator 2016 Winter Batch member launching the Revl Arc smart action camera. Designed in coordination with frogVentures, Sony, Ambarella and leading engineers with backgrounds at NASA, HP and Sikorsky Aircraft, the Revl Arc is available for preorder and will begin shipping in December. Revl was founded in 2015 and is based in San Francisco. For more information, please visit www.revl.com

eBrandValue, Inc. is a Mountain View, CA-based company that acts as a BI platform for brands and leverages social data to forecast sales and provide competitive intelligence. Its unique proprietary algorithm essentially captures consumer behaviour and brand affinities using social data to identify the most effective profile changing events. 

 eBrandValue has become a de facto forecaster of sales in many industries by accurately predicting and reporting the real-time sales, ROI, brand performance and market share-impact of brands in comparison to all of their competitors. These predictions are confirmed by Nielsen’s ScanTrack, which once again emphasises the catalytic impact of next-stage intelligent social media analysis to sales strategy.
 eBrandValue enables brands to measure the efficacy and ROI of their events and campaigns, and to track and analyse influencers within their industry. It also provides Meme-Based Netnographic Segmentation which reveals the dimensions that define a brand and encapsulate the nature of social media postings in the sector, thus allowing brands to track their positioning vis-à-vis competition in real-time.
 eBrandValue recently graduated from Y Combinator’s Winter’15 batch, and received press coverage at VentureBeat. Additionally, eBrandValue was also showcased as part of the Start Up Academy during Cannes Lions as one of the ten globally selected startups that are currently disrupting the marketing/agency business.


We're a mobile attribution and analytics provider, focused on helping app developers, marketers, and publishers find and grow their users. We track a bunch of metrics such as ad spend, ad revenue, in-app purchase revenue, subscription revenue, retention, etc. We also have a data warehousing product that lets our customers directly query the data we've collected. Experts at mobile advertising, need help with handling all of this data and making a very technical front-end more user-friendly.

Lob provides the building blocks for developers to automate the offline world. Enterprise companies use Lob’s suite of APIs to mail fully dynamic and personalized customer communications with print media. We provide insight into deliverability with piece-by-piece tracing and utilize our proprietary Print Delivery Network to streamline production across fully redundant nodes all over the country. Founded in 2013 and based in San Francisco, Lob is venture backed by Y Combinator, Polaris Partners, Floodgate, and First Round Capital. Find out more about Lob and what we’re up to by following our blog: https://lob.com/blog or visiting our website: https://lob.com.

mth sense focuses on finding solutions to "blind" ads. mth sense offers its users an audience library to target certain demographics and psychographics.

Videopixie is a marketplace for video production that allows users to have great video on the website, such as promotional videos and etc. Videopixie is a marketplace where you can hire the world’s best video professionals at a range of price points, to fit any budget. Retailers use Videopixie to make weekly product videos. Game companies use Videopixie to make trailers, using in-game footage, to air on national TV. Newly-weds use Videopixie to edit their five hours of ‘big-day’ footage into a five minute keepsake for life.

OneSignal is the leading omnichannel customer engagement solution, powering personalized customer journeys across mobile and web push notifications, in-app messaging, SMS, and email. Our easy-to-use interface empowers content creators to focus on quality user engagement instead of complex implementation. Our powerful platform enables over a million businesses to deliver 10 billion messages daily and 1 in 7 new apps launches using OneSignal! We support companies in 140 countries, including Zynga, USA Today, Bitcoin.com, Upwork, Tribune, and many more - from startups and small businesses just getting off the ground to established companies communicating with millions of customers.

Truva handles the busywork intelligently saving your sales team hours each week, so they can focus on what matters most - building and closing deals. Many teams have seen up to 25% increase in sales where Truva's AI agents automated tedious tasks such as email follow up, CRM data entry, and process optimizations.

Zyper is a machine learning-led community marketing tool that enables brands to identify and engage with the top 1% of their social following, turning them from passive followers to active advocates. These brand fans create authentic and emotive content, scaling peer-to-peer advertising in a unique way by uplifting market voice, engagement and social conversion. Neither micro-influencers nor bloggers, brand fans are real, social-savvy consumers who influence their immediate peer group and immerse themselves in your brand ecosystem. We target them at scale to give you the equivalent reach of one influencer but with the value of repeat content, authenticity and higher engagement.

ClearBrain (YC W18) is a startup building the first self-serve AI platform for growth marketing. We help companies automatically predict and retarget users when they are most likely to purchase. Fortune 1000 companies use ClearBrain’s automated machine learning platform to personalize experiences for hundreds of millions of user predictions - as effectively as Uber or Google. We’re led by the founding engineers of Google Ads and Optimizely’s data infrastructure teams, and backed by investors in Dropbox, Optimizely, and AdMob. We’re a deeply technical team who value humility and customer empathy above all. As a group we’re also pretty good at bowling, D&D, and Rubik’s cubes. We are building an advanced analytics platform with the challenge of making it accessible to a smart, capable clientele of growth experts that demands ease of use, utility, high availability and good responsiveness. You’ll join a startup environment where you'll be exposed to a variety of backend, frontend, machine learning frameworks in a fast-moving company!