Softwr

Networking · head to head

Kentik vs OPNsense

Kentik logo

Kentik

Networking

Network observability platform built on flow and traffic data, sold on annual-only contracts starting around $24,000/year

From
On request
Rated
-
Full reviewWebsite
OPNsense logo

OPNsense

Networking

FreeBSD-based firewall and routing platform with weekly updates and a full configuration API

From
Free
Rated
-
Full reviewWebsite

The short version

  • Only OPNsense has a free tier, so it costs nothing to try first.
  • Each has a real cost: Kentik contracts are annual only, so there is no monthly option for a team wanting to trial the platform under real production load before committing to a year of spend; OPNsense throughput depends entirely on hardware you selected yourself, and intrusion prevention at multi-gigabit rates will saturate a machine that handled plain firewalling fine, with no vendor sizing commitment to fall back on.
  • They diverge on capability: Kentik covers Flow-based traffic analysis, OPNsense covers Stateful firewall on pf.
  • Prices and features above were last checked on 1 September 2026.

Where they differ

Only the attributes on which Kentik and OPNsense actually diverge.

Attributes where Kentik and OPNsense differ
AttributeKentikOPNsense
Starting priceOn requestFree
Pricing modelAnnual contract only, per tierOpen source, no licence fee
Free tierNoYes
PlatformsWeb, APIx86-64 appliances, Virtual machines, Deciso hardware

Identical on both: user rating (Not yet rated), category (Networking).

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 Kentik

  • Flow-based traffic analysis
  • Synthetic testing
  • Cloud network monitoring
  • DDoS detection
  • API-driven querying

Only in OPNsense

  • Stateful firewall on pf
  • VPN suite
  • Suricata IDS and IPS
  • Full configuration API
  • High availability
  • Weekly update cadence

What people use each for

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

Kentik

  • A network engineering team at an ISP or large enterprise needing flow-level traffic visibility beyond basic uptime monitoringnot OPNsense
  • A cloud-heavy organisation wanting visibility into cloud provider network cost and performance across multiple providersnot OPNsense
  • A security or network operations team wanting DDoS detection layered on top of standard traffic monitoringnot OPNsense
  • A team needing synthetic testing alongside passive flow analysis in one platform rather than two separate toolsnot OPNsense

OPNsense

  • Replacing a small business firewall appliance whose renewal quote exceeded the cost of the hardwarenot Kentik
  • Branch offices where the firewall configuration must be produced by Ansible rather than by handnot Kentik
  • Sites that need WireGuard and intrusion prevention on the same box without separate feature licencesnot Kentik
  • A homelab or lab network needing VLAN routing, multi-WAN and DNS filtering on one machinenot Kentik

Where each one falls short

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

Kentik

  • Contracts are annual only, so there is no monthly option for a team wanting to trial the platform under real production load before committing to a year of spend
  • The Pro tier's $24,000/year starting price is a serious commitment relative to general infrastructure monitoring tools, and it is aimed specifically at flow-level traffic visibility rather than general host monitoring
  • Add-on modules for advanced DDoS protection, service provider analytics and the Firehose pipeline are priced separately, so real deployment cost frequently exceeds the Pro sticker price
  • Premier tier pricing is entirely quote-based, so organisations needing more than Pro's limits (50 users, 1,000 FPS, 120-day retention) cannot get a number without a sales conversation
  • It is a specialised flow and traffic analytics tool, not a general infrastructure monitoring platform, so most buyers will still need a separate tool like PRTG or Icinga for host and service uptime checks
  • Data retention is capped at 120 days for traffic and 45 days for forensic data even on Pro, which may be short for organisations with longer compliance or investigation requirements

OPNsense

  • Throughput depends entirely on hardware you selected yourself, and intrusion prevention at multi-gigabit rates will saturate a machine that handled plain firewalling fine, with no vendor sizing commitment to fall back on.
  • The weekly update cadence is good for security but means more change events than a team used to annual appliance firmware, and occasional regressions reach production installations.
  • FreeBSD underneath limits driver support compared with Linux, so recent network cards and some virtualisation drivers can be unsupported or slow.
  • The plugin ecosystem is uneven in quality; some plugins are maintained by a single contributor and can lag a major release, breaking a function you depended on.
  • Community support is a forum, so an outage at two in the morning on the free edition is your problem alone unless you bought the business subscription in advance.

Pricing, plan by plan

Kentik

On request
  • Pro$24000/year
    • 50 users
    • 1,000 flows per second baseline
    • 2.5M synthetics credits
  • Premier$undefined/year
    • 1,000 users
    • 5M synthetics credits
    • Custom dimensions and scheduled reporting

OPNsense

Free
  • OPNsense Community EditionFree
    • MIT licence with no feature restrictions
    • All VPN, IDS and HA features included
    • Weekly updates and two major releases a year
  • OPNsense Business Edition$undefined/year
    • Stabilised update track lagging community releases
    • Commercial support from Deciso
    • Additional enterprise plugins and configuration backup

Which should you pick?

Choose Kentik if

  • You need flow-based traffic analysis.
  • You work on Web, API.
  • You also want synthetic testing.
Kentik review

Choose OPNsense if

  • You need stateful firewall on pf.
  • You want to start without paying.
  • You work on x86-64 appliances, Virtual machines, Deciso hardware.
  • You also want vpn suite.
OPNsense review

Questions people ask

Is Kentik or OPNsense better?
Neither clearly leads. Kentik starts at On request and OPNsense at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Kentik or OPNsense?
OPNsense has a free tier; the other does not. Paid plans start at On request for Kentik and Free for OPNsense.
Does Kentik or OPNsense run on more platforms?
Kentik runs on Web, API. OPNsense runs on x86-64 appliances, Virtual machines, Deciso hardware.
Can I use OPNsense for free?
Yes. OPNsense has a free tier, so you can try it without paying. Kentik starts at On request.
What is Kentik best used for?
Kentik is most often used for a network engineering team at an isp or large enterprise needing flow-level traffic visibility beyond basic uptime monitoring, a cloud-heavy organisation wanting visibility into cloud provider network cost and performance across multiple providers, a security or network operations team wanting ddos detection layered on top of standard traffic monitoring, a team needing synthetic testing alongside passive flow analysis in one platform rather than two separate tools. Of those, a network engineering team at an isp or large enterprise needing flow-level traffic visibility beyond basic uptime monitoring and a cloud-heavy organisation wanting visibility into cloud provider network cost and performance across multiple providers are not what OPNsense is typically brought in for.
What can Kentik do that OPNsense cannot?
Kentik covers Flow-based traffic analysis, Synthetic testing, Cloud network monitoring, DDoS detection. OPNsense covers Stateful firewall on pf, VPN suite, Suricata IDS and IPS, Full configuration API.

Answered from the vendors’ own pages

Kentik: Is there a monthly billing option?

No, Kentik states contracts are annual only.

OPNsense: How is it different from pfSense?

It is a 2015 fork with an MIT licence, a fixed weekly release cadence, a complete configuration API and a different interface. Feature coverage is comparable; the release process and API are the real differences.

Kentik: What is the entry price?

Pro starts at $2,000/month billed as $24,000/year for 50 users and baseline flow and synthetics quotas.

OPNsense: Do I need the Business Edition?

Only if you want commercial support or a slower, stabilised update stream. No features are withheld from the community edition.

Kentik: Does Kentik replace general infrastructure monitoring tools like PRTG?

No, it is focused on flow-based traffic and network observability rather than general host and service uptime monitoring.

OPNsense: Can it handle a gigabit internet connection?

Plain firewalling on modest current hardware, comfortably. With Suricata inspection enabled, expect to need a considerably stronger CPU.

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