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Networking · head to head

OpenVPN vs OWASP ZAP

OpenVPN logo

OpenVPN

Networking

Open source VPN protocol with a commercial Access Server product priced per simultaneous connection

From
Free
Rated
-
Full reviewWebsite
OWASP ZAP logo

OWASP ZAP

Cybersecurity

Free, open-source web application scanner and intercepting proxy, now governed by the Software Security Project.

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: OpenVPN open source OpenVPN, while free, requires real technical skill to configure, secure and maintain without the Access Server admin layer; OWASP ZAP authenticated scanning of modern single-page applications is the hard part and ZAP makes you build it by hand: session handling, token refresh and login scripts are configured per application, and a misconfigured session means the scanner logs itself out and reports a clean result for pages it never reached.
  • They diverge on capability: OpenVPN covers Open source core, OWASP ZAP covers Intercepting proxy.
  • Prices and features above were last checked on 1 September 2026.

Where they differ

Only the attributes on which OpenVPN and OWASP ZAP actually diverge.

Attributes where OpenVPN and OWASP ZAP differ
AttributeOpenVPNOWASP ZAP
Pricing modelOpen source core is free; Access Server billed per simultaneous connectionfree
PlatformsLinux, Windows, macOS, iOS, AndroidDesktop, Cli, Api
CategoryNetworkingCybersecurity
FoundedUnknown2001

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in OpenVPN

  • Open source core
  • Access Server admin UI
  • Per-connection licensing
  • Free tier
  • Cross-platform clients

Only in OWASP ZAP

  • Intercepting proxy
  • Passive scanner
  • Active scanner
  • AJAX spider
  • Automation Framework
  • Headless daemon and REST API
  • Docker images
  • Add-on marketplace

What people use each for

The jobs each tool is most often brought in to do.

OpenVPN

  • A technical team wanting a fully free, self-configured VPN server using the open source protocol without any vendor relationshipnot OWASP ZAP
  • A small business wanting a supported, easier-to-administer VPN server, willing to pay per concurrent connection rather than per employeenot OWASP ZAP
  • An organisation with more staff than typical concurrent VPN usage, since Access Server bills only active simultaneous connections, not total accountsnot OWASP ZAP
  • An IoT or large-scale deployment needing custom Enterprise pricing above 2,000 connectionsnot OWASP ZAP

OWASP ZAP

  • Adding a baseline security scan to every application's pipeline where per-target commercial licensing would limit coverage to a handfulnot OpenVPN
  • Manual penetration testing that needs an intercepting proxy, request replay and fuzzing without a paid licence per testernot OpenVPN
  • Teaching developers what an attack against their own endpoint looks like, using a tool they can install themselvesnot OpenVPN
  • Pre-release regression scanning of an internal application that would never justify a commercial DAST subscriptionnot OpenVPN

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

OpenVPN

  • Open source OpenVPN, while free, requires real technical skill to configure, secure and maintain without the Access Server admin layer
  • Per-connection billing on Access Server means usage spikes, such as an all-hands remote day, can push simultaneous connections over a licensed limit and block new connections until usage drops or the plan is upgraded
  • OpenVPN's traditional hub-and-spoke architecture routes traffic through a central server, unlike mesh VPN tools like Tailscale or NetBird that establish direct peer-to-peer connections where possible, which can add latency
  • Client configuration and certificate management for the open source version is more manual and error-prone than newer VPN tools with zero-config onboarding
  • Access Server pricing above the Growth tier reverts to custom Enterprise quoting, so very large deployments lose the pricing transparency of the lower tiers
  • The protocol's throughput is generally lower than newer kernel-integrated protocols like WireGuard under equivalent conditions, which matters for high-bandwidth use cases

OWASP ZAP

  • Authenticated scanning of modern single-page applications is the hard part and ZAP makes you build it by hand: session handling, token refresh and login scripts are configured per application, and a misconfigured session means the scanner logs itself out and reports a clean result for pages it never reached.
  • There is no support contract in the product, so when a scan breaks the day before a release the escalation path is a GitHub issue and a community chat, which is not an answer that satisfies a delivery manager or an auditor who wants a named responsible party.
  • Active scanning sends genuine attack traffic, so it can create records, trigger emails, exhaust rate limits or destabilise a fragile environment, and pointing it at production without prior agreement produces an incident rather than a test result.
  • Output needs triage: passive rules generate large volumes of low-severity informational findings about headers and cookie flags that bury the few results that matter, and a team without someone tuning the rule set stops reading the report within a few sprints.
  • As a dynamic scanner it can only test what it can reach, so authorisation flaws between accounts, business logic abuse and anything behind an undiscovered endpoint go unreported, and a passing ZAP scan is evidence of nothing more than the absence of the classes of bug it looks for.

Pricing, plan by plan

OpenVPN

Free
  • Access Server FreeFree
    • Up to 2 simultaneous connections
    • All features included
  • Access Server Growth$7/month
    • Per simultaneous connection beyond the free tier
    • Annual billing
  • Access Server Enterprise/IoT$undefined/month
    • Custom pricing for 2,000+ connections

OWASP ZAP

Free
  • Free & Open SourceFree
    • Full functionality
    • Active & passive scanning
    • Spider

Which should you pick?

Choose OpenVPN if

  • You need open source core.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, iOS, Android.
  • You also want access server admin ui.
OpenVPN review

Choose OWASP ZAP if

  • You need intercepting proxy.
  • You want to start without paying.
  • You work on Desktop, Cli, Api.
  • You also want passive scanner.
OWASP ZAP review

Questions people ask

Is OpenVPN or OWASP ZAP better?
Neither clearly leads. OpenVPN starts at Free and OWASP ZAP at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, OpenVPN or OWASP ZAP?
OpenVPN starts at Free and OWASP ZAP at Free.
Does OpenVPN or OWASP ZAP run on more platforms?
OpenVPN runs on Linux, Windows, macOS, iOS, Android. OWASP ZAP runs on Desktop, Cli, Api.
Can I use OpenVPN for free?
Both have a free tier, so you can try either at no cost before committing.
What is OpenVPN best used for?
OpenVPN is most often used for a technical team wanting a fully free, self-configured vpn server using the open source protocol without any vendor relationship, a small business wanting a supported, easier-to-administer vpn server, willing to pay per concurrent connection rather than per employee, an organisation with more staff than typical concurrent vpn usage, since access server bills only active simultaneous connections, not total accounts, an iot or large-scale deployment needing custom enterprise pricing above 2,000 connections. Of those, a technical team wanting a fully free, self-configured vpn server using the open source protocol without any vendor relationship and a small business wanting a supported, easier-to-administer vpn server, willing to pay per concurrent connection rather than per employee are not what OWASP ZAP is typically brought in for.
What can OpenVPN do that OWASP ZAP cannot?
OpenVPN covers Open source core, Access Server admin UI, Per-connection licensing, Free tier. OWASP ZAP covers Intercepting proxy, Passive scanner, Active scanner, AJAX spider.

Answered from the vendors’ own pages

OpenVPN: Is OpenVPN free?

The open source protocol and software are free under the GPL; Access Server, the commercial packaged product, charges per simultaneous connection beyond a free 2-connection tier.

OWASP ZAP: Is it still called OWASP ZAP?

The project left OWASP in August 2024 and is now governed by the Software Security Project, with core development sponsored by Checkmarx. The tool is now just ZAP, though most existing documentation, courses and search results still use the OWASP name.

OpenVPN: What counts as a connection for billing purposes?

A simultaneously active connected device, not a registered user account or total device count; unlimited accounts and devices can be created but only the licensed number can be connected at once.

OWASP ZAP: Is it free for commercial use?

Yes. It is Apache 2.0 licensed, with no per-application, per-scan or per-user cost, and it can be used and modified commercially without a licence agreement.

OpenVPN: How does OpenVPN compare with WireGuard-based tools like Tailscale?

OpenVPN uses a traditional hub-and-spoke VPN architecture rather than the mesh, peer-to-peer approach used by newer tools like Tailscale or NetBird.

OWASP ZAP: Can it replace a penetration test?

No. It automates checks for known vulnerability classes against endpoints it can reach. It does not reason about business logic, chain findings into an attack, or test authorisation between accounts, which is most of what a tester actually does.

OWASP ZAP: Does it run in CI?

Yes, through the official Docker images and the Automation Framework, which defines scan jobs in YAML so configuration lives in the repository. A baseline passive scan is the usual starting point because it is fast and non-intrusive.

OWASP ZAP: How does it compare to Burp Suite?

Burp Suite Professional is the more polished manual testing tool and has a stronger scanner and extension ecosystem, but it is licensed per tester and Burp Suite Enterprise per target. ZAP is the better fit where cost per target is the binding constraint; many teams use both.

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