Google Custom Search JSON API vs SerpApi
The Custom Search JSON API is closed to new sign-ups and is set to shut down on January 1, 2027. If you are an existing customer, start a move now. For a new build, pick SerpApi, which is open and publishes its plans. Hyperresearch Answers is our editorial choice when an AI agent needs search: instead of a raw results page, one call returns a short answer with quotes checked against their pages.
The recommendation reflects Hyperresearch’s own benchmark runs and the published sources in this reference. Hyperresearch is our product. This is not a hands-on test of every tool.
Side by side
| Google Custom Search JSON API | SerpApi | |
|---|---|---|
| Pricing | Free up to 100 queries a day. Beyond that, $5 per 1,000 queries, with a cap of 10,000 a day | Free plan: 250 searches a month. Paid plans from $25 per 1,000 down to about $2 per 1,000 at large volume |
| What it returns | Google Programmable Search results as JSON, for a search engine you configure | Structured JSON or Markdown results from Google and other engines |
| Sources and coverage | Google Programmable Search Engine index, limited to sites you configure | Google, Bing, Baidu, DuckDuckGo, Yahoo, Yandex, Naver, Brave and Qwant |
| Citations and verification | Results, not cited answers | Results, not cited answers |
| API and MCP | REST JSON API | REST API. No official MCP server on the page we read |
| Limits | 100 free queries a day; 10,000 a day cap on paid use | Hourly throughput is 20% of monthly volume on plans under 1 million searches |
| Best for | Existing customers with a current integration, until the shutdown date | New builds that need Google and other engines |
The shutdown changes the choice
Google's Custom Search JSON API is no longer open to new sign-ups. Google's documentation says existing customers have until January 1, 2027, to move to another solution, when the service is discontinued.
If you already run this API, plan the migration now. Test your queries on the replacement, check result quality, and keep a fallback in place. A short trial is safer than a last-minute switch in January.
What a replacement looks like
SerpApi covers Google and several other engines through one REST API. It publishes a free plan of 250 searches a month and paid plans that work out to about $25 per 1,000 on the smallest tier. Those per-1,000 figures are our calculation from its plan prices.
Custom Search was a search engine you configured. SerpApi returns results from the live engines, so the results will not match one-for-one. Check that your ranking logic still works before you move.
Think about what Custom Search did for you. If you used it to search a fixed list of sites, check whether SerpApi's engine results cover those sites well enough. If you used it for open web search, the switch may be simpler, but the results will still differ.
Other options
If your agent needs a checked answer rather than a list of results, consider Hyperresearch Answers. It returns one short answer with quotes that match their source pages. On our own runs it scored 89% on BrowseComp. Those are Hyperresearch's results, not an independent test.
Neither SerpApi nor Custom Search returns cited answers, so your code must check and cite sources either way.
A migration test should start now, not in December. Pick twenty or thirty queries that your product runs today and run them through SerpApi. Compare the top results with what Custom Search returned. Where they differ, decide whether the difference matters to your users or whether you need to adjust your ranking or filtering logic. Keep the old integration running until the replacement passes that check. If you have a large volume, get a price from SerpApi's plan list before you commit, and remember that the free plan is 250 searches a month, which is small for production traffic.
Choose Google Custom Search JSON API or SerpApi?
- You already run Custom Search and need a bridge before January 1, 2027
- You want a service that is open to new customers today
- You need Google results across several engines
- You are building new and want an open, published price list
- You need Bing, Yandex or other engines alongside Google
- You want to avoid a shutdown deadline
Where Hyperresearch fits
Custom Search is closing, and SerpApi returns raw results. If your agent needs a checked answer, Hyperresearch Answers is our editorial pick.
Questions & answers
When does Custom Search JSON API stop?
Google's documentation says it is discontinued on January 1, 2027 for existing customers. New sign-ups are closed. Check Google's current page before you plan.
Is SerpApi a direct replacement?
Not exactly. Both return Google-style results as JSON, but Custom Search searched sites you configured, while SerpApi queries live search engines. Test your queries before you switch.
Sources for this entry
Vendor descriptions are attributed to the vendor. Prices change; confirm with each vendor.
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Cite this entry
https://bestserpapi.com/compare/google-custom-search-json-api-vs-serpapi/