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Signals API reference
GET /api/signals returns AltFTool's catalogue of search-demand signals for online tool ideas as JSON: each record has a name, the search query, a category, an estimated monthly search volume, an opportunity score out of 100, competition, momentum, region and related AltFTool pages. Filter with q, category and momentum, sort by opportunity, volume or name. It is limited to 60 requests a minute and is meant to be called from a server.
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Search-demand signals for tool ideas: name, query, category, estimated search volume, opportunity score, competition and momentum.
Matches name, query, summary and category. Trimmed, first 100 characters.
Exact category match. Empty means all.
Exact momentum match. Empty means all.
Unknown values fall back to opportunity.
GEThttps://www.altftool.com/api/signalsCode for this request
curl -sS -H "Accept: application/json" 'https://www.altftool.com/api/signals'
Query parameters
- q: free text matched against name, query, summary and category (first 100 characters, case-insensitive).
- category: exact match - AI & Content, Documents, Business, Developer or Security.
- momentum: exact match - Surging, Rising or Stable demand.
- sort: opportunity (default), volume or name. Anything else falls back to opportunity.
Response fields
- dataAsOf: the date the estimates were compiled. Show it next to any figure you republish.
- count: number of results after filtering.
- results[]: slug, name, query, category, summary, searchVolume, opportunityScore, competition, momentum, region, relatedPaths[], actions[].
How to read the numbers
searchVolume is an estimate compiled on the dataAsOf date, not a live count. opportunityScore is AltFTool's own 0-100 ranking of demand against competition. Use them to compare ideas with each other, not as exact traffic forecasts.
Limits, CORS and caching
| Endpoint | Returns | Browser CORS | Rate limit | Cache |
|---|---|---|---|---|
| GET /api/signals | Signals catalogue | Same origin only | 60 requests per minute per client | CDN 1 hour, then stale for up to 24 hours |
Read from each route's source code on 2026-11-01.
Signals API reference: questions and answers
How fresh is the signals data?
Each response carries a dataAsOf date. The catalogue is a curated snapshot updated by hand, not a live feed.
Why does my browser block the response?
/api/signals sends no CORS header, so another origin's browser JavaScript cannot read it. Call it from your server or a serverless function.
What does a 429 mean?
You sent more than 60 requests in a minute. Wait for the Retry-After seconds. With an hour of CDN caching there is rarely a reason to call it that often.
More developer reference
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