Buyer's guide · updated September 2026
The best website vulnerability scanners in 2026
Nine tools for finding what is exposed on a live site, from a thirty-second check to a full enterprise DAST, compared on what they find, what they cost, and how much setup they need. We make one of them. It is first on the list with its limits stated, because it answers a narrower question than most of the others.
- What can a stranger reach on my app, right now, free: Prbl
- Full dynamic scan, free, will learn it: OWASP ZAP
- Professional testing: Burp Suite
- Fast checks across many hosts: Nuclei
- Managed, continuous, with a report: Intruder or Detectify
- Enterprise DAST: Acunetix or Burp DAST
- Is my site already hacked: Sucuri SiteCheck
At a glance
| Tool | Best for | Free? | Time |
|---|---|---|---|
| Prbl Thirty-second surface check for AI-built apps | Founders and small teams who deployed an app built with AI tools and want to know what a stranger can reach, right now, with no setup | Free, no account | About 30 seconds |
| OWASP ZAP Open-source DAST | Anyone who wants a full, free dynamic scanner and is willing to learn it | Fully open source | Minutes to hours depending on scope |
| Burp Suite The professional's toolkit, plus a DAST product | Security professionals and pentesters; Burp DAST for enterprises that want it automated at scale | Community edition is free but limited; Professional is per user per year; DAST is enterprise | Manual, or scheduled with DAST |
| Nuclei Template-based scanner by ProjectDiscovery | Engineers who want fast, scriptable checks for known issues across many hosts | Open source; cloud platform is paid | Seconds to minutes |
| Nikto Classic web server scanner | Quick checks of server-level misconfigurations and dangerous files | Open source | Minutes |
| Intruder Managed external vulnerability scanning | Small and mid-size companies that want continuous scanning of their external surface with a clean report and no ops | Trial; paid per target | Scheduled, continuous |
| Detectify Crowdsourced attack surface and web app scanning | Teams with many subdomains who want continuously updated checks from a bug bounty community | Trial; paid | Scheduled, continuous |
| Acunetix (Invicti) Enterprise DAST | Enterprises that need automated, verified web scanning with compliance reporting across many applications | No free tier | Scheduled |
| Sucuri SiteCheck Malware and blacklist checker | Site owners who suspect their site is already compromised, especially WordPress | Free check; paid cleanup and firewall | Seconds |
Prbl
Best for: Founders and small teams who deployed an app built with AI tools and want to know what a stranger can reach, right now, with no setup. Free: Free, no account. Time to result: About 30 seconds.
- Checks the things AI-built apps actually get wrong: keys in the JavaScript, dashboards that render without login, exposed .env and .git, a database readable with the public key
- Read-only and needs only the URL; no crawler configuration, no authentication setup
- Classifies public-by-design keys correctly instead of crying wolf
- Every finding comes with the fix, and the repo scan finds the line that caused it
- Numbers behind it: 4,740 live apps probed, 261 exposed, data published
- Not a full crawler; it does not fuzz every input for injection the way a DAST does
- Active database and API probes are limited to verified owners
- One app at a time; no fleet dashboard on the free tier
OWASP ZAP
Best for: Anyone who wants a full, free dynamic scanner and is willing to learn it. Free: Fully open source. Time to result: Minutes to hours depending on scope.
- The reference free DAST: spider, active scan, fuzzing, intercepting proxy
- Automation framework and Docker images for CI
- Huge community, add-on marketplace
- No cost at any scale
- Real learning curve; a default active scan against a modern SPA needs configuration
- Noisy without tuning
- No managed service; you run and maintain it
Burp Suite
Best for: Security professionals and pentesters; Burp DAST for enterprises that want it automated at scale. Free: Community edition is free but limited; Professional is per user per year; DAST is enterprise. Time to result: Manual, or scheduled with DAST.
- Industry standard for manual web testing
- Best-in-class scanner in Professional
- Extensions for nearly everything
- Burp DAST scales the same engine across many apps
- Community edition cannot run the automated scanner
- Professional is a per-seat cost and assumes expertise
- Enterprise DAST is priced accordingly
Nuclei
Best for: Engineers who want fast, scriptable checks for known issues across many hosts. Free: Open source; cloud platform is paid. Time to result: Seconds to minutes.
- Thousands of community templates for CVEs, misconfigurations and exposures
- Very fast, built for scanning at scale
- Templates are YAML, easy to write your own
- Great for continuous checks in CI
- Finds what has a template; not a general crawler or fuzzer
- Output needs triage
- Cloud dashboard is a separate paid product
Nikto
Best for: Quick checks of server-level misconfigurations and dangerous files. Free: Open source. Time to result: Minutes.
- Fast, simple, checks thousands of known dangerous files and server issues
- Still useful for exposed admin panels and default files
- Runs anywhere
- Signature-based and old; little understanding of modern JavaScript apps
- Very noisy; loud on the target's logs
- No application-level logic
Intruder
Best for: Small and mid-size companies that want continuous scanning of their external surface with a clean report and no ops. Free: Trial; paid per target. Time to result: Scheduled, continuous.
- Set it and forget it; results prioritised and explained
- Combines infrastructure, web and emerging-threat checks
- Good for compliance evidence
- Attack surface discovery
- Priced per target, adds up with many apps
- Less depth on application logic than a manual test
- Not built around application code or fixes
Detectify
Best for: Teams with many subdomains who want continuously updated checks from a bug bounty community. Free: Trial; paid. Time to result: Scheduled, continuous.
- Payloads sourced from ethical hackers, updated constantly
- Strong subdomain and asset discovery
- Good coverage of modern web frameworks
- Paid, priced for companies
- Findings still need someone to fix them
- Overkill for a single app
Acunetix (Invicti)
Best for: Enterprises that need automated, verified web scanning with compliance reporting across many applications. Free: No free tier. Time to result: Scheduled.
- Proof-based scanning confirms many findings automatically
- Broad vulnerability coverage including out-of-band checks
- Integrations with ticketing and CI
- Mature reporting
- Expensive
- Heavy for small teams
- Setup and tuning is a project
Sucuri SiteCheck
Best for: Site owners who suspect their site is already compromised, especially WordPress. Free: Free check; paid cleanup and firewall. Time to result: Seconds.
- Instant, no setup
- Checks malware, defacement, blacklists and outdated CMS software
- Paid cleanup service if you are already infected
- Answers a different question: is the site already infected, not is it exposed
- Little value for a modern app on Vercel or Netlify
- No application security checks
How we evaluated
What question each tool answers, how much setup it needs before the first useful result, what you can use without paying, and whether it is safe to point at production. Claims about other tools come from their public documentation and pricing pages as of September 2026; tell us if we got something wrong. Our own data on how deployed AI-built apps fail comes from probing 4,740 live apps, published in full.
Frequently asked questions
What is the best website vulnerability scanner?
It depends on the question you are asking. Is my deployed app exposing something a stranger can reach right now: Prbl, thirty seconds, free. Full dynamic testing of every input: OWASP ZAP if you will learn it, Burp Suite if you are a professional, Acunetix or Burp DAST if you are an enterprise. Continuous managed scanning with a report: Intruder or Detectify. Is my site already infected: Sucuri. Most small teams pair a fast surface check on every deploy with a full scan before big releases.
Which website vulnerability scanners are free?
OWASP ZAP, Nuclei and Nikto are open source. Burp Suite Community is free but cannot run the automated scanner. Sucuri SiteCheck's basic check is free. Prbl's live URL scan is free with no account, and the deeper database and API probes are free for verified owners.
Is a vulnerability scanner safe to run on my own site?
Passive and read-only scanners like Prbl and Sucuri make ordinary requests and are safe on production. Active scanners like ZAP, Burp and Acunetix send attack payloads and can create data, trigger emails, or slow the site; run those against staging or with care. Never run an active scanner against a site you do not own or have permission to test.
What is the difference between a vulnerability scanner and a penetration test?
A scanner is automated and finds known classes of issues quickly and repeatedly. A penetration test is a person, usually with a scanner in hand, finding the logic flaws and chained issues automation misses. Scanners are for every deploy; a pentest is for a release, a compliance requirement, or a launch that matters.
Why does an AI-built app need a different kind of scanner?
Because it fails differently. Traditional DAST is built to fuzz form inputs for injection. AI-built apps mostly leak through configuration: the Supabase key with row level security off, the dashboard that renders without a session, the .env file the host is serving, the key in the bundle. We probed 4,740 of them and 1 in 18 handed something private to an anonymous request, none of it via injection. A scanner built for that surface finds it in seconds; a crawler built for forms can miss it entirely.
The fastest way to compare scanners is to run one. Paste your URL and see what a stranger can reach, in thirty seconds, free.
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