How to Look Up a YC Company by ID, Batch, or Slug

If you landed here from a search like ai29973, ai29605, or another ai##### string, you are usually trying to identify a specific Y Combinator company—often from Google Search Console traffic, a spreadsheet, or an internal reference—not a batch code like W24.

On Guide Startups, those codes map to our numeric company_id in the database. The prefix ai is how many lookup queries are typed; the digits are the ID. Example: ai29973 → company ID 29973 → company page /companies/arva-ai-29973 (Arva AI).

This guide explains every reliable way to find a YC company on the directory: by ID, by URL slug, by batch, and by name or tagline.

Each company in our dataset has a stable company_id (integer). Public URLs are not /companies/ai29973; they use a readable slug plus that ID for uniqueness:

/companies/{company-name-slug}-{company_id}

Examples:

• ID 29973 → /companies/arva-ai-29973
• ID 29798 → /companies/ai-29798
• ID 29605 → /companies/educato-ai-29605

The trailing number is always the company_id. The name segment comes from the company title, so slugs vary in length. If you only know the ID, use the companies search and enter 29973 or ai29973—you will be taken straight to the matching profile when it exists.

Note: Y Combinator’s official directory uses its own URLs and IDs. Guide Startups is an independent educational directory; IDs here are specific to this site’s data model.

If you already have a slug (from a link, sitemap, or search result), open it directly:

https://guidestartups.tech/companies/your-slug-here

Slugs are lowercase, hyphenated, and end with the numeric ID. You can confirm you have the right company by checking the batch, description, and founders on the page.

Company pages link out to:

• Batch — e.g. /batches/w25 for that cohort
• Industries — tag pages such as /industries/fintech
• Year founded — /year/2024 when data is available
• Founders — /founders profiles by name

For long-tail searches that quote a tagline (“instant SaaS management,” “Palantir for healthcare AI”), start on /companies and search words from the description; slugs are based on company names, not taglines.

Batch codes are not the same as ai##### company IDs. A batch code looks like W24 (Winter 2024), S21 (Summer 2021), X25 (Spring 2025), or F26 (Fall 2026).

To browse everyone in a cohort:

1. Go to /batches and pick a batch, or open /batches/{slug} (e.g. /batches/w24).
2. Scan the grid or use pagination for large batches.

For what W / X / S / F mean and the annual schedule, read YC batches explained and Y Combinator batch schedule. Confusing a batch code with a company ID is a common mistake—batch pages list hundreds of companies; an ai##### query points to one company.

When you do not have an ID, filter the directory:

These paths help competitive research and investor benchmarking. For what “industry vertical” means, see what are industry verticals.

Use ID or slug lookup when you have a precise reference (ai29973, a shared link, or a slug from email).

Use /companies search when you have a company name, keyword from a tagline, or industry tag. Search matches company name, short description, tags, and numeric ID.

Browse batches or industries when you are exploring a cohort or vertical without a target company yet.

Use YC’s official directory (ycombinator.com/companies) when you need YC’s canonical listing or Launch YC posts [1]. Guide Startups adds batch/year/industry navigation and founder pages tuned for research workflows on this site.

1. Strip the prefix. ai29973 → ID 29973.
2. Open /companies and type 29973 or ai29973 in the search box. If the company is in our dataset, you jump to its profile.
3. Or construct the slug pattern. If you know the company name (e.g. from YC), try /companies/{name-slug}-29973 in the browser.
4. Cross-check batch and tags on the company page to confirm it matches what you expected from search.
5. If nothing appears, the company may not be in our dataset yet, or the ID may refer to another system—verify on YC’s directory [1].

High-impression ai##### queries with zero clicks in Search Console often mean users need a clearer landing page—direct ID search on /companies is the fastest path on Guide Startups.

Many searches combine a person + company or a quoted tagline + Y Combinator. Those are not ID lookups:

• Founder name → how to find YC founders or browse /founders, then open the company page from the founder profile.
• CEO / leadership → company page founder section and external LinkedIn; see our upcoming guides on founder research for more detail.
• Tagline-only query → use company search with distinctive words from the quote, or browse the relevant industry.

Do not expect ai##### codes to resolve founder names—use name or company search instead.

Y Combinator company lookup on Guide Startups works through numeric company_id values (often searched as ai#####), readable slugs ending in that ID, and browse paths by batch, year, industry, and founder. For an unknown ai29973-style code, search /companies with the digits or full string, or open /companies/*-29973 once you know the name.

For batch naming (W24 vs. company ID), read YC batches explained. For a full map of browse routes, see how to browse Y Combinator companies or start from the company index.