Shodan OSINT and Censys Review: Internet Scan Data Compared
Shodan OSINT work starts from a simple idea: search the internet's devices and services, not its web pages. Shodan and Censys both scan the public internet and let you search what they find, from open ports and software versions to TLS certificates. This review compares them using their official pricing pages, documentation and public guidance, checked on 10 October 2026.
- Hosts, ports, banners, certificates
- Free accounts on both
- Shodan plans from $49 one-time
- Censys credits from $100
Shodan OSINT means using Shodan's search engine for internet-connected devices to see which hosts, ports and services an organization exposes. Censys does similar work with a strong focus on certificates and threat hunting. Both suit security teams, researchers and authorized testers. Shodan sells a $49 one-time membership and monthly plans; Censys offers 100 free credits a month, paid credits and enterprise plans.
What Are Shodan and Censys?
Two commercial search engines built on continuous internet-wide scanning: Shodan indexes service banners from connected devices; Censys indexes hosts, certificates and web properties.
Shodan calls itself "a search engine for Internet-connected devices" and explains the difference from web search this way: "Shodan crawls the Internet whereas Google crawls the World Wide Web" (Shodan Help). Its products include the main search engine, Monitor for tracking your own exposed devices, Maps, Images, the free InternetDB lookup for open ports on an IP address, CVEDB for vulnerability data, Trends for historical data, and an exploit search (Shodan products).
Censys grew out of ZMap, an internet scanner created at the University of Michigan in 2013, and became a standalone company in 2017 (About Censys). Today its platform is aimed at security operations, threat hunting and attack surface management, with natural-language search and an AI assistant included in every paid platform plan.
How Shodan OSINT Searches Work: Banners, Hosts and Certificates
You search indexed scan results with filters such as organization, network, port, product or certificate details, and both services return what was observed and when.
Shodan's core data is the banner: metadata a service returns when contacted, such as server software, version and supported options (Shodan Help). Searches use a filter syntax rather than plain language; Shodan notes that typing a phrase like "power plant" will not give proper results. Censys lets you look up hosts, certificates and web properties, and charges credits per lookup and query.
Typical OSINT questions these tools answer for a defender or an authorized tester:
- Which IP addresses and services does our organization or a named supplier expose, and since when?
- Which of our hosts run software versions with known vulnerabilities?
- Which certificates mention our domains, revealing forgotten subdomains or look-alike infrastructure?
- Does a suspicious server share certificates or configuration with infrastructure seen in a phishing campaign?
Shodan vs Censys: Key Features Compared
Shodan is the more accessible entry point for individuals; Censys is built around team plans for security operations and threat hunting.
| Feature | Shodan | Censys |
|---|---|---|
| Core data | Service banners from internet-connected devices | Hosts, certificates and web properties from internet-wide scanning |
| Free use | Free account with a free API plan | 100 credits a month that expire monthly |
| Self-serve paid entry | $49 one-time membership | Credit packages from $100; credits valid 12 months |
| Own-asset monitoring | Shodan Monitor, from 16 IPs on membership | Attack surface management, quoted separately |
| Vulnerability data | CVEDB; vuln filter from Small Business plan | CVE and vulnerability data on all platform plans |
| Team plans | Single-user plans; Enterprise custom | Core and Adversary Investigation from 5 users; Security Operations unlimited |
Sources: Shodan billing, Censys pricing, Censys credits.
Shodan and Censys Pricing
Shodan publishes fixed monthly prices from $69 plus a $49 lifetime membership; Censys prices its platform plans through sales and sells credits from $100.
| Shodan plan | Price | Query credits a month | Scan credits / monitored IPs |
|---|---|---|---|
| Membership | $49 one-time | 100 | 100 / 16 |
| Freelancer | $69 a month | 10,000 | 5,120 / 5,120 |
| Small Business | $359 a month | 200,000 | 65,536 / 65,536 |
| Corporate | $1,099 a month | Unlimited | 327,680 / 327,680 |
| Enterprise | Custom | Unlimited | Unlimited |
Shodan's page lists commercial use from the Freelancer plan up and says annual subscriptions are available through sales (Shodan, checked 10 October 2026).
Censys lists three platform plans, Core, Adversary Investigation and Security Operations, with prices through sales; they differ by users, data history (from one month to twelve months or more) and threat-data access. Credit packages start at $100. Free users pay 1 credit per host or certificate lookup, 5 per standard query and 8 per regex query (Censys pricing; Censys docs).
Using Shodan for OSINT Reconnaissance Responsibly
Searching indexed data is passive, but what you do next is not: probing, logging in or exploiting what you find requires the system owner's authorization.
Looking up records in Shodan or Censys does not send traffic to the target; the services already did the scanning. The legal line is crossed when a user connects to, logs in to or tries to exploit a system they found without permission, which can breach laws such as the US Computer Fraud and Abuse Act. Requesting an on-demand scan with Shodan scan credits is also active testing and should cover only assets you own or are authorized to test.
This matters most for operational technology. CISA warns that exposed OT devices "are quickly found by searching for open ports on public IP ranges with search engine tools" and tells operators to remove OT connections from the public internet (CISA, May 2025). Utilities and other critical infrastructure operators should use these tools to find and close their own exposures, and report third-party findings through coordinated disclosure rather than probing them.
Who They Suit and Who They Do Not
They suit security teams, researchers, journalists studying infrastructure and authorized testers; they are not people-search tools.
- Good fit: defenders mapping their external attack surface; threat intelligence analysts pivoting on attacker infrastructure; researchers measuring exposure trends; red teams inside a written scope; investigators tracing who operates a phishing or scam server.
- Poor fit: finding information about private individuals; users who need answers without learning filter syntax; teams that need verified ownership of every IP address, which scan data alone cannot prove.
Limitations: Stale Data, Attribution and Legal Limits
Scan data is a snapshot, IP ownership is often unclear, and both platforms meter heavy use through credits.
- Timing. Each record reflects when the service was last seen. A port may have closed, or a cloud IP may now belong to someone else.
- Attribution. Hosting providers, CDNs and shared cloud ranges make it easy to attribute a host to the wrong organization. Confirm ownership through DNS, certificates and registry data before acting.
- Version guesses. Software versions come from banners, which can be modified or hidden, so vulnerability matches need confirmation.
- Credits and filters. Free tiers limit searches, result pages and filters; Shodan reserves the vuln filter for Small Business and above.
- Sensitive findings. Exposed cameras or control systems belonging to others should be reported, not explored or published.
Alternatives to Shodan and Censys for OSINT
Other scan search engines cover similar ground, and recon tools can pull Shodan or Censys data into a wider workflow.
- Other scan search engines: ZoomEye, FOFA, Netlas, ONYPHE and LeakIX index similar data; all are supported as sources in theHarvester (README). Check each provider's terms and pricing.
- theHarvester and Recon-ng: free recon tools that can query Shodan, Censys and others with your API keys.
- SpiderFoot: automated OSINT scanning that combines many sources.
- Maltego: graph analysis for pivoting from hosts to domains, certificates and organizations.
Our OSINT tools guide groups these by investigation task.
Need the Answer, Not the Tool?
If you need to know which exposures matter and who owns a suspicious server, an analyst-led review turns scan data into verified findings.
Shodan and Censys show what is visible. Deciding which exposures are yours, which are exploitable and what to fix first takes verification and context. Our red team OSINT reconnaissance maps your external exposure under written authorization, and our threat intelligence and incident response OSINT teams pivot on attacker infrastructure after an incident. Every report gets senior analyst review, scoped at a fixed quote.
For the wider picture, see how our OSINT services for cyber teams fit together.
Find Out What Your Organization Exposes
Send us the domains, IP ranges and brands in scope. We verify what is exposed, who owns it and what to fix first.
Shodan and Censys OSINT FAQ
I'm new to Shodan OSINT and want to see what my company exposes on the internet — can I do that with a free account, or do I need to pay before results are useful?
You can start free. All Shodan accounts include a free API plan, and Censys gives free users 100 credits a month. For a meaningful look at your own exposure, Shodan's $49 one-time membership adds 100 query credits a month, 20 result pages and monitoring for 16 IP addresses (Shodan). Larger estates or vulnerability filtering need a monthly plan. Confirm that every host you find really belongs to you before acting on it.
Our security lead asked whether we should standardize on Shodan or Censys for attack surface work — what is the practical difference, and is it worth paying for both?
Shodan is easier to start with: published prices, a lifetime membership and single-user monthly plans. Censys is built for teams, with platform plans from five users, longer data history and threat-hunting features, priced through sales. Their scans differ, so each sees things the other misses. Many teams use one as the main platform and keep a free or credit-based account on the other for cross-checks.
I found what looks like an exposed industrial control panel belonging to a local utility while searching Shodan — is it legal to click through and look, and what should I do?
Do not connect to it, log in or test it. Viewing the indexed record is passive, but interacting with a system you do not own can breach computer misuse laws such as the US Computer Fraud and Abuse Act. Report it to the utility's security contact or your national CERT through coordinated disclosure. CISA warns that exposed OT devices are found quickly with search engine tools (CISA), so early reporting helps.
We received a phishing email and want to know who runs the server behind the link — can Shodan or Censys tell us who owns it, or only what is running on it?
They mostly tell you what is running and how it is configured: open ports, software, certificates and when it was seen. That lets you pivot to other servers sharing the same certificate or configuration, which often reveals a wider campaign. Ownership usually needs more: hosting provider records, domain registration history, payment trails and links to known actors. Treat a shared hosting IP with care, since many unrelated sites can sit behind it.
I run a small consultancy and want to use Shodan data in client reports — which plan allows commercial use, and are there rules about publishing what I find?
On Shodan's billing page, commercial use is listed from the Freelancer plan at $69 a month upward; the one-time membership does not list it (Shodan). Read each vendor's terms before reusing data. In reports, limit findings to the client's authorized scope, avoid publishing other organizations' exposed systems and share vulnerable details only with the people who will fix them.
Sources and Notes
- Shodan: plans and billing
- Shodan Help Center: What is Shodan?
- Shodan: products
- Censys: pricing
- Censys docs: credits for Free and Starter users
- Censys: about
- CISA: Primary Mitigations to Reduce Cyber Threats to Operational Technology
- 18 U.S. Code § 1030 (Computer Fraud and Abuse Act)
- theHarvester README (supported scan data sources)
Sources checked 10 October 2026. This review is based on official documentation, pricing pages and public guidance; OSINT-S has not run either tool for this review and has no affiliation with Shodan or Censys.