Custom Search API vs SerpApi

The whole migration is one line

Your code keeps its path, its parameters and its parser. The address changes, and the key.

# Before
curl "https://www.googleapis.com/customsearch/v1?key=$GOOGLE_KEY&cx=$CX&q=open+source+vector+databases"

# After
curl "https://api.specstream.ai/customsearch/v1?key=$SPECSTREAM_KEY&cx=$CX&q=open+source+vector+databases"

Moving to SerpApi means a new request to serpapi.com/search and a parser that reads organic_results in place of items. On SpecStream there is nothing to map.

What stays the same

GET /customsearch/v1 reads q, num from 1 to 10 and start, and queries.nextPage gives the next start. exactTerms, orTerms, siteSearch and hq shape the search as they do on Google. cx is accepted and not used, because SpecStream searches the whole live web. The key works in key=, in the X-Goog-Api-Key header or as a Bearer token.

The most accurate web search API in the world

The SpecStream Search API scores a 97.9 F-score on all 1,000 official SimpleQA Verified questions, with 978 correct. On WideSearch it scores 64.0 item F1 and 43.4 row F1 on all 200 official tasks, and the Extract API scores 0.908 F1 on WCXB. SerpApi's own post reports 97.6% on the same benchmark, on the 960 questions it kept after setting 40 aside. The scores and the method are at specstream.ai/benchmarks.

$5 per 1,000 searches from top-ups that do not expire

Google's paid rate is $5 per 1,000 queries and it stops at 10,000 a day. SpecStream charges the same $5 per 1,000 with no daily limit: 10,000 searches a day cost $50. On SerpApi's Production plan 15,000 searches cost $150 a month, $10 per 1,000, and the searches belong to that month. A SpecStream top-up never expires, and a call stopped by a 429 charges nothing.

About one second a search, at up to 8,800 a minute

Every results list route runs the fast search unless the call asks for page text or results past the first ten. On November 9, 2026 production took 1 to 20 fast searches a second and answered 718 of 720: the median was 0.82 s at 1 search a second and 1.07 s at 20 a second, and the 95th percentile stayed between 1.09 and 1.73 s. One account takes up to 8,800 searches a minute, and a call over that gets a 429 with Retry-After and is not charged.

Zero retention on any key

Set zero_retention when you create a key, or later. A search made with that key keeps no request text and no answer after the reply: it is not in the history, its answer is not reused for another call, and its log lines carry neither. The charge keeps the account, the key, the request ID, the price and the time.

curl -X POST https://api.specstream.ai/v1/account/keys \
  -H "Authorization: Bearer $SPECSTREAM_API_KEY" -H "Content-Type: application/json" \
  -d '{"name": "production", "scopes": ["account:read", "finds:spend"], "spend_cap_cents": 500000, "zero_retention": true}'

Search, pages and rows on one key

A product that calls Custom Search still has to read the pages and build its own records. On SpecStream the same key reads up to 20 pages or documents a call with the Extract API at $0.80 per 1,000 pages, and runs Deep Search, which returns every match on the live web as structured rows at 5¢, 15¢ or $1 a row. 10,000 rows with 5 facts each cost $500, and the most a run can cost is approved before it starts. Save a request and it reruns hourly to yearly, with each row labeled changed, unchanged or no longer matching.

Vertex AI Search (Agent Search)

Google's own suggestion on the Custom Search page, for searching up to 50 domains. Search Standard costs $1.50 per 1,000 queries and Search Enterprise $4.00, with 10,000 free queries a month, on a new endpoint, POST https://discoveryengine.googleapis.com/v1/...:search. For full web search Google asks you to contact it. SpecStream searches the whole live web on the path your code already calls.

Grounding with Google Search in the Gemini API

A Gemini model searches Google and writes the answer. On Gemini 3 and newer it costs $14 per 1,000 search requests after 5,000 free a month, and it returns the model's answer with citations, not a result list. A SpecStream call returns the answer with its page and every result in rank order, for $0.005.

SerpApi

Google results pages as JSON, by monthly plan: Starter at $25 for 1,000 searches, Developer at $75 for 5,000, Production at $150 for 15,000. The request and the reply follow SerpApi's own format. On SpecStream $25 pays for 5,000 searches in the Custom Search format your code already reads.

Serper

Google results sold as prepaid credits with no monthly subscription, from $1.00 per 1,000 on the 50k pack. The first 2,500 queries are free, no credit card. SpecStream answers Serper's own call at https://api.specstream.ai/serper/search, in Serper's JSON, for $5 per 1,000 searches.