▌ GlossaryGlossary / CID / Knowledge Graph ID

CID / Knowledge Graph ID

Q: How do I find my business's CID?

Open your business on Google Maps, look at the URL — the cid= query parameter is the CID. If you're an owner replying to a review, the URL also contains the CID. Or use the resolver above with any Maps link.

Also: Customer ID · Knowledge Graph ID · Google CID

A CID (Customer ID, also called Knowledge Graph ID) is the unique numeric identifier Google assigns to a business inside its Knowledge Graph. Unlike Place ID — Google's public-facing ID — the CID appears in long-form Maps URLs and pairs one-to-one with a business across Google Search, Maps, and Knowledge Panel.

Local SEO Foundational · 3 min read

Try it · free

Paste a Google CID, hex CID, Place ID, or Google Maps URL. The resolver detects the format, extracts the IDs, and surfaces them in every form you might need.

Try:

Detected:Google Maps URL

CID (decimal)

12517453345498537179

CID (hex)

0xadb6ed7f56f71cdb

Google Maps URL

https://www.google.com/maps?cid=12517453345498537179

→Maps URL contained a `cid=` parameter — the business's Google CID.
→Place ID is not embedded in this URL format. Get it via Google's Places API using the CID, or use any local-SEO API that accepts CID directly.

Skip the conversion entirely. The Google Business Profile API accepts both CID and Place ID — same response, no conversion step required.

See the Google Business Profile API

Why CIDs exist

Google maintains a single canonical identifier for every business in its Knowledge Graph. The Place ID is the API-friendly version (alphanumeric, used in Google Places and Maps API requests). The CID is the original internal numeric ID — a 64-bit integer that appears inside Google's own URL parameters and inside the Knowledge Graph's structured records.

If you've ever seen a long Google Maps URL containing a cid= query parameter, that's a CID. If you've ever pulled business data via the Places API, the response includes a Place ID. They identify the same business — but they're not interchangeable as strings, and several local-SEO workflows require both.

Where you'll see a CID

CIDs show up in three places most local-SEO practitioners encounter:

Google Maps URLs: links of the form google.com/maps?cid=12345678901234567890 resolve directly to a specific business listing.
Knowledge Panel deep links: the share link from a Knowledge Panel often includes the CID as a kgmid parameter.
Review reply URLs: when you reply to a Google review as a business owner, the URL contains the CID of your profile.

The Place ID, by contrast, shows up almost exclusively in API responses (Google Places, Google Business Profile) and in Google's official Place ID Finder tool.

Converting between CID, Place ID, and Maps URL

Most local-SEO tools (and our own Business Profile API) accept the Place ID format. If you only have a CID — pulled from a Maps URL, or from a client who shared a Knowledge Panel link — you need to convert.

The conversion is deterministic: every CID has exactly one Place ID and vice versa. The resolver tool above takes any of the three inputs (raw CID, Place ID, or Maps URL) and outputs the other two formats. For API workflows, you'll almost always feed the Place ID into your endpoint of choice.

CIDs in the agent era

Agents working with local-SEO data routinely encounter both ID formats. A user pasting a Google Maps link into a Claude prompt is handing the agent a CID. The agent that's been wired to a Place-ID-keyed endpoint (almost every third-party local-SEO API) needs to convert first. The agent prompt pattern becomes: *resolve the CID, then call the data endpoint*.

The Local SEO Data API treats the conversion as a free pre-call: any endpoint accepts either format and resolves transparently. But for agents calling third-party APIs that aren't as forgiving, the resolver tool above is the bridge.

Related terms

Glossary

Place ID

The public, API-friendly identifier for a business location.

Glossary

Google Business Profile

The canonical business listing on Google.

Glossary

Knowledge Graph

Google's structured database — where CIDs live.

Glossary

Knowledge Panel

The branded info box that surfaces CID-linked data.

Related APIs

API

Google Business Profile API

Pull NAP, hours, categories, photos — Place ID input.

API

Google Reviews API

Full review history for any Place ID.

FAQ

What's the difference between a CID and a Place ID?+

Both identify the same business uniquely. A CID is a 64-bit integer used in Google's internal systems and in Maps URLs (cid=...). A Place ID is an alphanumeric string used in Google's public APIs (Places, Business Profile). Every business has exactly one of each, and they're convertible.

How do I find my business's CID?+

Open your business on Google Maps, look at the URL — the cid= query parameter is the CID. If you're an owner replying to a review, the URL also contains the CID. Or use the resolver above with any Maps link.

Can I use a CID directly with the Places API?+

No. Google's Places API expects Place ID format. Convert the CID first (the tool above does it), then pass the Place ID to the API.

Does Google publish a CID-to-Place-ID conversion API?+

Not as a documented endpoint, but the mapping is deterministic and reversible. Several open-source libraries handle it, and our resolver does the same conversion locally — no API call required.

Why do agents need to handle CIDs?+

When a user pastes a Google Maps URL into an agent prompt, the URL contains a CID, not a Place ID. The agent has to convert before calling any Place-ID-keyed endpoint. Building this conversion into the agent's pre-flight step (or using an API that accepts both formats) prevents the most common workflow break.

Want this at API scale?

Once you have the Place ID, pull NAP, hours, categories, photos, and reviews in one call.

See Google Business Profile API