Pricing
The whole price.
On one page.
No quote wall, no discovery call, no “contact sales.” One published per-device price — the same number for a 10-device office and a 1,000-device fleet. Move the slider; see your bill.
Your monthly bill
50 devices × $4.00 · effective $4.00/device
Devices
tier $4 · 50–249
The ladder
Volume pricing, published — no negotiation.
Your whole fleet gets the best rate it qualifies for — no minimums, prorated daily.
What every device gets
One price. The whole box, watched its own way.
A server, a hypervisor and a printer don’t speak the same language — so Arqos doesn’t force them into one table. Each device is watched in its own terms, and it’s all the same per-device price. No add-ons, no “that’s the Enterprise tier.”
Servers & VMs
60-second agent
- [•]CPU, memory and per-volume disk, once a minute
- [•]“Disk full — with what?” names the largest directory in the alert
- [•]The runaway process, named, while CPU is pinned
- [•]Uptime + boot cause: Windows Update vs. power loss, told apart
- [•]Any service, port or process you name — up / listening / running
Hypervisors
ESXi / VMware
- [•]Every datastore's capacity — with cluster-shared SANs de-duplicated
- [•]The full VM roster: running, heartbeat-lost, or powered off
- [•]Committed memory and true host uptime (survives an snmpd restart)
- [•]Pages on a filling datastore, a failed sensor, or clock drift
Switches · routers · firewalls
read-only SNMPv2c
- [•]Per-port status, link speed and ↓/↑ traffic
- [•]Interface error rates, physical uplinks split from virtual
- [•]A port that drops when it should be up opens one incident
- [•]No agent on the gear — one on-site probe watches them all
Printers
read-only SNMP
- [•]Toner and supply levels per cartridge, in plain language
- [•]Monthly page ledger — the lease-billing number, kept for you
- [•]Jam, open-door and low-paper states surfaced
- [•]Onboard a printer at 8% toner and it pages on first sight
Hardware & environment
self-reported inventory
- [•]Model, serial and firmware — a live inventory, not a spreadsheet
- [•]Temperature, fan and voltage sensors where the gear exposes them
- [•]Clock drift measured against server time
- [•]Read-only config visibility — nothing is ever scanned or probed
Service exposure
config visibility
- [•]Every network service a device advertises about itself
- [•]Cleartext and legacy protocols flagged with a quiet advisory
- [•]Telnet, FTP, SNMPv1, SMBv1 — “prefer X / disable if unused”
- [•]Self-reported from the device, never a port scan
And for the whole fleet
A dashboard that stays quiet
Healthy machines collapse into summaries; the worst thing is already at the top. Drill fleet → site → device, worst-first, every hop.
Down in ~2 minutes, resolved automatically
Absence-based detection catches power loss and cut uplinks. The alert auto-resolves and confirms recovery, so a 2 a.m. page can't haunt your morning.
Alerts that route and escalate
Email and iOS push today, with per-channel routing, escalation, and daily / weekly digests. Snooze a device or set a maintenance window without going blind.
Evidence your insurer will accept
Uptime reports and incident dossiers, exportable — the paper trail lenders and cyber-insurance underwriters ask for, generated instead of assembled by hand.
Scoped, site by site
Every location its own view, every viewer scoped to only what they should see, and alert thresholds you can tune. Bring a new site online without touching a firewall.
iOS and desktop, in your pocket
The whole fleet on an iPhone and a menu-bar monitor on the desktop — the same worst-first story, wherever you are.
How both sides win
Ghost devices are free
A device silent for 30 days is auto-archived and billing stops — by itself, no ticket. We only charge for machines we're actually watching.
Month-to-month
Cancel anytime. No 1-, 3-, or 5-year contracts and no auto-renew traps. If we stop earning the fee, you stop paying it.
Your rate is locked
The per-device price you join at never increases while you stay subscribed. We're deleting the renewal-hike letter.
One published price
This page is the pricing — for a 10-device business and a 1,000-device fleet alike. No discovery call, no wondering what the last customer paid.
Coming from Nagios?
A serious tool. Here’s the honest tradeoff.
Nagios has watched infrastructure since 1999, and we’re not going to pretend otherwise. But most of what it costs never prints on its pricing page — so here’s the comparison laid out flat, the parts that favor us and the parts that don’t.
| Nagios XI | Arqos | |
|---|---|---|
| How you pay | Perpetual license, $2,595–$4,690 — published in blocks that start at 100 nodes | $3–5 / device / month, first 3 free — billed to the exact count |
| A 40-device shop buys | 100 nodes — 60 you'll never watch | 40 devices — nothing you don't watch |
| The server it runs on | Yours to stand up, patch, back up, and secure | None — hosted and patched by us |
| Getting started | Config files, plugins, and an NRPE agent per host | One command per server (~60s); a probe covers the network gear |
| If the monitor is breached | NRPE and event handlers can run commands on your hosts | Nothing runs — the agent has no command channel |
| Commitment | Perpetual license + annual maintenance | Month-to-month, cancel anytime |
The license is the smallest line.
The sticker is the one cost that’s easy to see. The server it runs on, the hours to build and maintain the config, the upgrade cycle, and the risk of running a command-capable monitor on your own network — those are the real bill, and none of them print on a pricing page. Arqos moves all of them to us for one flat per-device fee.
Held for years at 150+ devices, Nagios’s perpetual license can win on sticker alone — we’ll tell you that to your face. Below that, and once you count the server and the hours, it isn’t close.
Where Nagios still earns its place
- [•]Battle-tested since 1999, with a plugin ecosystem that can monitor almost anything you can script.
- [•]Self-hostable — the right call when a mandate requires infrastructure data to stay on your own hardware.
- [•]Deep, fully custom checks and business-process / SLA reporting a young hosted product doesn't match yet.
If that’s you — a monitoring engineer on staff and an on-prem mandate — keep Nagios; it’s a rational choice. Arqos is for the other teams: the ones that want the watching without running the watcher.
The landscape, honestly
Every other tool on this list can run commands on your machines.
It’s the category norm — remote commands, event handlers, script actions, collector remoting. Convenient until the day the vendor is breached, at which point the tool watching your network can also command it. Arqos gave that capability up on purpose: the agent has no code to execute anything, so there is nothing to hijack.
| Tool | How they price | Where it runs | Can it run commands on your machines? |
|---|---|---|---|
| Nagios XI | perpetual, $2,595–$4,690 | self-hosted | yes — NRPE + event handlers |
| Zabbix | free OSS + paid support | self-hosted | yes — remote commands |
| Icinga | free OSS + paid support | self-hosted | yes — event handlers |
| Checkmk | per service, from €190/mo | self-hosted / cloud | yes — MRPE on host |
| Observium | free / ~£200/yr | self-hosted | no — SNMP poll only |
| OpManager | per device, $95–$4,595/yr | self-hosted | yes — workflow scripts |
| SolarWinds | per node, from ~$7/node/mo | self-hosted / SaaS | yes — external-program actions |
| PRTG | per sensor, $200–$1,642/mo | self-hosted / hosted | yes — script sensor |
| Datadog | per host, $15–23/host/mo | SaaS | yes — checks shell out |
| LogicMonitor | per unit, $16–53/mo (quote) | SaaS | yes — collector scripting |
| Auvik | per device, quote-only | SaaS | yes — remote command |
| Arqos | $3–5 / device, published | SaaS | no — no channel exists |
market scan july 2026 — vendor docs + published pricing. execution is standard across the category; Zabbix and Icinga ship it disabled by default, the commercial tools ship it enabled. Arqos and Observium are the only two that can’t do it at all — and Observium is a self-hosted SNMP poller you run and patch yourself.
For engineers
Your tech team will have sharper questions.
Good. The technical dossier answers them: the full wire protocol, the complete list of every field that leaves a machine, the threat model, and the exact commands to verify every claim yourself — no trust required.
[•]Request the technical dossierFair questions.
The billing questions owners and IT teams actually ask — answered plainly.
Is this really the price?
Yes. The slider above is the billing engine, not a marketing estimate. What you see is what the invoice says.
Do I sign a contract?
No. Month-to-month, cancel anytime. The first 3 devices are free forever, so you can run it for real before you pay anything.
We already run Nagios, Zabbix, or PRTG — why switch?
You might not need to. If you have an engineer who enjoys running it and a reason to keep it on-premises, those tools are capable. Teams move to Arqos for three reasons: nothing to host or patch, a per-device bill with no node-block minimums, and a monitoring agent that physically can't be turned against the network it watches. If none of those hurt today, there's no rush.
What counts as a device?
Anything that reports: a server, a hypervisor, or a piece of network gear watched by the probe. One device, one line, one rate — no sensor counting.
What happens when a device goes away?
Billing follows reality. Decommission a server and it stops reporting; after 30 quiet days it auto-archives and drops off the bill with no action from you.
See your whole fleet by this afternoon.
Early access is open to a small number of IT teams. First 3 devices free.