Custom Search Client logo

Custom Search Client

Custom Search Client

Bing Custom Search lets you define a custom domain subset and run Bing search against it — for vertical or enterprise search.

Visit site ↗Health checked 9h ago
Use it when

Built on Bing crawl + ranking — higher quality than self-built search

Watch for

Sunsets 2025-08-11 — migration required

First check

Configure an instance on customsearch.ai (add domains, tune ranking) to get the customconfig ID. GET /v7.0/custom/search?q=...&customconfig=...

Auth
CORS
No
HTTPS
Yes
Signup
?
Latency
173 ms
Protocol
REST
Pricing

Uptime · 30-day window

Probes: 1Uptime: 100%Avg latency: 173ms
01

About this API

Custom Search is the Bing Search API product for "I have a fixed set of domains and want search over them" scenarios. Configure at customsearch.ai — allowlist/denylist domains, adjust per-domain weighting (boost corporate site to the top), pin specific URLs. Backend uses Bing's crawl index and ranking — far superior to self-built Elasticsearch + naive BM25. Sunsets 2025-08-11 with the entire Bing Search API family. Migration: Azure AI Search is Microsoft's recommended successor, though it's a different product shape.

02

What you can build

  • 1Enterprise knowledge-base search (SharePoint + corporate domains)
  • 2Vertical search engine (e.g. legal sites only)
  • 3Brand + partner aggregated search
03

Strengths & limitations

Strengths

  • Built on Bing crawl + ranking — higher quality than self-built search
  • Precise domain allowlist/denylist
  • Ranking adjustments and result pinning supported

Limitations

  • Sunsets 2025-08-11 — migration required
  • Only indexes publicly crawlable content
04

Example request

Generic template — replace <endpoint> with the real path from the docs.
curl https://microsoft.com/<endpoint>
05

Getting started

Configure an instance on customsearch.ai (add domains, tune ranking) to get the customconfig ID. GET /v7.0/custom/search?q=...&customconfig=...

06

FAQ

How does Custom Search compare to Azure AI Search?+

After 2025-08-11 only Azure AI Search remains. They work differently: Custom Search filters Bing's index; AI Search indexes your content into Azure-managed search.

Can I search intranet content?+

No — Bing must be able to crawl it. For intranets, use Azure AI Search or Microsoft Search.

07

Technical details

CORS: NoHTTPS: YesSignup: ?Open source: No
Auth type
unknown
Pricing
unknown
Protocols
REST
SDKs
python, javascript, csharp
Response time
173 ms
Last health check
5/12/2026, 7:37:52 AM
08

Tags

09

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