AltF Developers
Open data API reference
AltFTool publishes two open datasets as JSON with CORS open to any origin: exam photograph and signature upload specifications for Indian exams, and an index of every /transform converter page. You may copy, republish and build on both, even commercially, if you show a visible "Source: AltFTool" credit linking the record's own page. Full field documentation lives on the Open Data page.
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- Code in 5 languages
API explorer
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Open dataset: photo and signature upload rules for Indian exams, each record with its source notification and confidence level.
This endpoint takes no parameters.
GEThttps://www.altftool.com/api/open-data/exam-photo-specsCode for this request
curl -sS -H "Accept: application/json" 'https://www.altftool.com/api/open-data/exam-photo-specs'
Endpoints
- GET /api/open-data/exam-photo-specs - one record per exam with assets[] (format, KB range, pixels, DPI), background rules and a source block with confidence.
- GET /api/open-data/transform-converters - one record per converter: slug, title, category, from, to and url.
Attribution in one line
Put a visible "Source: AltFTool" link next to the figures, pointing at the record's page_url (exams) or url (converters) - not at the API endpoint and not at the home page. Each dataset includes an attribution_example block you can copy.
Caching
Both responses are static and cached for 24 hours in browsers and the CDN, and served stale for up to 7 days while they refresh. Fetching once a day is enough.
Limits, CORS and caching
| Endpoint | Returns | Browser CORS | Rate limit | Cache |
|---|---|---|---|---|
| GET /api/open-data/exam-photo-specs | Exam photo and signature specs | Any origin (Access-Control-Allow-Origin: *) | No per-client limit; served from cache | Browser and CDN 24 hours, stale for up to 7 days |
| GET /api/open-data/transform-converters | Format converter index | Any origin (Access-Control-Allow-Origin: *) | No per-client limit; served from cache | Browser and CDN 24 hours, stale for up to 7 days |
Read from each route's source code on 2026-11-01.
Open data API reference: questions and answers
Can I fetch these from the browser?
Yes. Both endpoints send Access-Control-Allow-Origin: *, so fetch() from any website works.
Is there a licence name like CC BY?
No named licence is claimed. The terms are written out in plain words on the Open Data page: free use, including commercial, with a visible credit link to the record's page.
Is the converter index a conversion API?
No. It lists converter pages. Each conversion runs on its own page; there is no endpoint that converts a file.
More developer reference
- Free JSON API quickstart (no API key)Call AltFTool's free public JSON API in a minute: no key, no sign-up. Working cURL, JavaScript, Node.js, Python and PHP examples with caching and 429 handling.
- Signals API referenceGET /api/signals returns search-demand signals for tool ideas: query, category, search volume estimate, opportunity score and momentum. Parameters, fields and examples.
- oEmbed provider referenceAltFTool's oEmbed endpoint turns a pasted tool URL into a live widget in WordPress, Ghost and any oEmbed consumer. Parameters, response, errors and a live tester.
- Embed free tool widgets on your siteEmbed free AltFTool calculators, converters and generators on your site with one iframe, a responsive wrapper or a WordPress block. Builder, preview and rules.
- Feeds, sitemaps and llms.txtEvery machine-readable AltFTool file: RSS feed, XML sitemap, Google News sitemap, llms.txt, llms-full.txt, ai.txt and robots.txt, with refresh times and uses.
- Rate limits, 429s and cachingAltFTool API rate limits and cache headers per endpoint, what a 429 response contains, and copyable retry-with-backoff code that honours Retry-After.
Free developer tools
Requests and APIs
JSON and data
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