12 Best Intruder Alternatives in 2026 (Real Pricing & Free Options)

If the thing that drove you off Intruder was the price, start here. HostedScan runs external and internal vulnerability scans on websites, servers, networks and APIs, and it actually publishes its pricing, from about $39 a month.

It is built on trusted open-source engines (OpenVAS, OWASP ZAP, Nuclei) wrapped in a clean dashboard with alerts, scheduled scans and audit-ready reports. You get most of what Intruder's entry tier does, at a fraction of the cost and without a sales call. For a small team or a freelancer managing client sites, this is the obvious first stop.

The honest catch: It does not have Intruder's AI pentesting or quite the same polish, and the old free-forever plan is now a 14-day trial. But for transparent, low-cost scanning, nothing here beats it.

Detectify is the closest match to Intruder's external-scanning positioning, and detectify vs intruder is the comparison people search for most. It continuously maps your internet-facing assets, domains, IPs, apps and APIs, then scans them using research crowdsourced from ethical hackers.

Where Intruder is broad, Detectify goes deep on external attack-surface management: finding the forgotten subdomain, the exposed staging site, the quiet misconfiguration. It publishes starting prices, around €90 a month for application scanning and €302 for surface monitoring, so you know the cost before you call. For surface monitoring specifically, it is sharper than Intruder.

The honest catch: It is priced in euros with a minimum order value, and it focuses on the external surface, so it is less of an all-in-one than Intruder. Pick it when attack-surface monitoring is the priority.

Astra blends an automated DAST scanner with on-demand manual penetration testing and the compliance evidence auditors want (SOC 2, ISO 27001, HIPAA, PCI-DSS). Pricing is transparent and starts around $69 a month.

The pitch is one platform for both the continuous scanning and the once-a-year human pentest, with a clean vulnerability dashboard and a publicly verifiable security certificate at the end. For a startup that needs a compliance badge and real testing without juggling two vendors, it is a strong, honestly-priced pick.

The honest catch: The deeper manual-pentest work sits on higher tiers, and there is no free plan, only a demo. But you see the price before you commit, which most of this list will not give you.

Nessus is the scanner most security professionals cut their teeth on, and it is still the benchmark for scan accuracy and plugin coverage. Tenable publishes its prices, Nessus Professional is $4,790 a year, and there is a free version to start with.

Nessus Essentials scans up to 5 IP addresses free, now a time-limited license rather than the old free-forever tier, but still enough to learn the tool or cover a small network. Step up to Tenable Vulnerability Management for the cloud platform, dashboards and asset tracking. If you want depth and accuracy over a slick managed experience, Nessus is the standard everything else is measured against.

The honest catch: It is a scanner, not the hands-off managed service Intruder is, so you do more of the driving. The free Essentials tier is now capped at 5 IPs and time-limited, and the full platform is enterprise-priced.

Qualys VMDR (Vulnerability Management, Detection and Response) is the enterprise heavyweight: cloud-based scanning, risk prioritisation and built-in patch orchestration in one platform. It is what large, compliance-heavy organisations standardise on.

The strength is breadth, agents, network scanners, cloud connectors and patching all under one roof, with the dashboards and reporting a big security team needs. It scales to huge asset estates that would make Intruder's per-target pricing painful. This is a platform you grow into, not a five-minute setup.

The honest catch: Pricing is contact-sales only, and the platform's breadth means a real learning curve and rollout. Overkill for a small site; right for a large org.

Rapid7 InsightVM is the other enterprise mainstay, known for live dashboards, risk scoring and tight remediation workflows that hand developers and IT exactly what to fix. It now sits inside Rapid7's wider Exposure Command.

Where it shines is turning a scan into action: prioritising by real-world risk, tracking remediation, and integrating with ticketing so fixes actually happen. For a security team that lives in the data and wants to drive remediation, not just generate a report, InsightVM is built for that.

The honest catch: Unlike Qualys, Rapid7 publishes per-asset pricing (around $22 an asset a year, with a 512-asset minimum), but it is still enterprise-weight: you are buying a programme, not a quick scanner. Small teams will find it heavy.

Invicti (formerly Netsparker) is a web-application scanner built around proof-based scanning: it tries to safely confirm a vulnerability is real before it tells you, which cuts the false positives that waste an AppSec team's time.

It scans web apps and APIs at scale, plugs into CI/CD, and auto-verifies findings so you chase fewer ghosts. For a team whose risk lives in custom web applications rather than network assets, Invicti is more focused than Intruder's broad coverage. Acunetix is its lighter sibling from the same company.

The honest catch: Pricing is contact-sales and aimed at organisations, not individuals. It is a web-app DAST, so it does not cover the network and cloud surface Intruder does.

Acunetix, also by Invicti, is one of the longest-running web vulnerability scanners, twenty-plus years of DAST. It crawls and tests web apps and APIs for OWASP-class issues like SQL injection and cross-site scripting, fast and with good accuracy.

Think of it as Invicti's more accessible tier: the same lineage, aimed at mid-size teams that want a capable web-app scanner without the full enterprise platform. It handles modern single-page apps and API formats well. Pricing is not public, but third-party estimates put the entry around $7,000 a year for a handful of targets.

The honest catch: Still contact-sales, still web-app-focused (not network or cloud), and licensed per target. A web-app specialist, not an all-in-one Intruder replacement.

If your budget is zero and you are comfortable in a terminal, Nuclei is the answer. From ProjectDiscovery, it is a free, open-source scanner that uses a huge community library of YAML templates to test apps, infrastructure and networks for known vulnerabilities.

It is fast, scriptable and trusted, with nearly 30,000 GitHub stars, and the template model means new exploit checks land quickly. It pairs naturally with the rest of ProjectDiscovery's recon tools. For the big "free vulnerability scanner" search this is the honest answer, alongside OpenVAS / Greenbone (a full open-source scanning engine) and OWASP ZAP for web apps.

The honest catch: It is a command-line tool with no managed dashboard, scheduling or alerts, you build that around it. Great for technical users, not a point-and-click replacement for Intruder.

Snyk is excellent, but it is not really an Intruder alternative. It is developer-first security: it scans your code, open-source dependencies, containers and infrastructure-as-code for vulnerabilities, inside the IDE and CI/CD, before you ship.

Where Intruder scans your running, deployed assets from the outside, Snyk scans your source and supply chain from the inside. Plenty of teams run both. It has a free tier and paid plans from about $25 per developer per month. If your risk is in the code you write and the packages you pull in, Snyk is right, but its core is not scanning your live perimeter.

The honest catch: It is a different category (software composition and static analysis), not a network or external vulnerability scanner. Buy it to secure code, not to replace Intruder's perimeter scanning.

Wiz is the fast-growing cloud security platform (a CNAPP), now owned by Google Cloud after a 2026 acquisition, and again, it is a different tool. It connects to your cloud accounts and builds a graph of misconfigurations, exposures and attack paths across AWS, Azure and GCP.

If your estate is mostly cloud infrastructure, Wiz gives you context Intruder does not: how a low-risk misconfiguration chains into a real attack path. But it is agentless cloud posture management, not an external or web scanner. It overlaps with Intruder's cloud-scanning piece, not the whole product.

The honest catch: Contact-sales, enterprise-priced, and cloud-only. A complement to a scanner, not a replacement for one.

Pentera does automated security validation: instead of just listing vulnerabilities, it safely tries to exploit them, like an automated pentester, to show which ones a real attacker could actually use. That is a layer beyond scanning.

It answers a different question to Intruder: not "what vulnerabilities exist" but "which of them are genuinely exploitable in my environment". Mature security teams run validation on top of scanning to cut the noise and prioritise. It is powerful, and priced for enterprises.

The honest catch: Contact-sales and aimed at mature security programmes. It validates exposure; it is not the day-to-day scanner most people want when they search for an Intruder alternative.