
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.
Built on Bing crawl + ranking — higher quality than self-built search
Sunsets 2025-08-11 — migration required
Configure an instance on customsearch.ai (add domains, tune ranking) to get the customconfig ID. GET /v7.0/custom/search?q=...&customconfig=...
Uptime · 30-day window
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.
What you can build
- 1Enterprise knowledge-base search (SharePoint + corporate domains)
- 2Vertical search engine (e.g. legal sites only)
- 3Brand + partner aggregated search
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
Example request
curl https://microsoft.com/<endpoint>Getting started
Configure an instance on customsearch.ai (add domains, tune ranking) to get the customconfig ID. GET /v7.0/custom/search?q=...&customconfig=...
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.
Technical details
- 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
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