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Subdomains by Jsmon
Last updated 2026-09-10 · benchmark measured 2026-09-10 — deterministic & reproducible
API service for querying a database of over 3.5 billion indexed subdomains.
Is Subdomains by Jsmon production-ready?
Legit.Show scores Subdomains by Jsmon 69 out of 100 — the simple average of its 5 measured frames. Legit.Show ran its deterministic 7-Frame production-readiness benchmark on Subdomains by Jsmon (public-surface assessment), measured from the public surface with no LLM in the scoring path. Its strongest frame is Discoverability; its weakest is Privacy. 5 of the seven frames returned a score; Performance and Accessibility were not measurable on this service and are recorded as null — not as zero. Every frame it averages is published with its evidence on the Legit.Show listing.
The 7 Frames
- Performance — not measurable on this service (null — not scored as 0)
- Accessibility — not measurable on this service (null — not scored as 0)
- Security — 80/100
- Privacy — 0/100
- Reliability — 90/100
- Standards — 75/100
- Discoverability — 100/100
What we measured
- Security headers present: HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy.
- No Content-Security-Policy.
- Served over HTTPS with a valid certificate.
- Real Lighthouse performance run — 234 ms to first byte.
- Returns a proper 404 for unknown routes.
- 2 of 3 sampled routes reachable.
- No privacy policy found.
- Sets cookies / loads scripts with no consent prompt.
Who built it
encodedguy (@3nc0d3dGuY) · product account @jsmonsh
Who it's for
Security researchers · Red teams · Bug bounty hunters · ASM vendors · Security providers
Pricing
Free: $0/month (3 queries/day, 100 results max); Pro: $20/month (5,000 queries/month, 10,000 results max); Max: $100/month (50,000 queries/month, 10,000 results max); Enterprise: Custom pricing
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