coturn the software is free and open-source. Running it is not free — you pay for the VPS, the bandwidth, and your own time setting it up and keeping it healthy. The break-even depends on your traffic and how you value your time.

ExpressTURN vs Self-Hosted coturn

Q: How long does coturn setup take?

A first-time setup including DNS, certificates, firewall rules, and validation typically takes a developer 4–8 hours. Setting it up correctly across multiple regions for low-latency relay is a multi-day project.

Q: Does ExpressTURN run coturn under the hood?

ExpressTURN's relay servers run a hardened, multi-region TURN deployment. The wire protocol is standard RFC 5766/8656 — your client code doesn't care what software is on the other end.

Q: When should I pick self-hosted coturn?

When you have strict data-locality requirements that forbid third-party relays, when your traffic is large enough that bandwidth at hyperscaler prices is cheaper than $9/TB amortized, or when you need on-prem deployment for compliance reasons.

Honest tradeoffs. Real numbers. We'll tell you when to self-host and when to pay $9.

TL;DR

Self-host coturn if you have strict data-locality requirements, plan to push more than ~10 TB/month of relayed traffic, or simply enjoy operating infrastructure. Use ExpressTURN if you'd rather ship your product. The break-even point is roughly 5–10 TB/month of relayed bandwidth and a few hours of saved ops time.

Side-by-side

Dimension	Self-Hosted coturn	ExpressTURN
Software cost	$0 (open-source)	$9/month for 5 TB, $0 for 1 TB free
VPS cost (single region)	$5–20/month + bandwidth overage	included
Bandwidth	~$0.005–0.01/GB at budget VPS providers; ~$0.09/GB on AWS/GCP egress	$0.0018/GB amortized at $9/5TB
Initial setup time	4–8 hours; days for multi-region	~5 minutes
Ongoing ops (TLS renew, OS patches, capacity)	2–4 hours/month if nothing breaks	none
Global coverage	one region per VPS you provision	20+ regions out of the box
DDoS / abuse handling	your problem	handled upstream
Data locality	total control	shared third-party relay (DTLS-SRTP encrypted; opaque to relay)
SLA	whatever your VPS provider offers	no formal SLA at $9 — but production traffic since 2018

Real cost of self-hosting at small scale

A common low-end starter setup: one $5/month Hetzner / OVH / DigitalOcean VPS with a generous bandwidth allowance (1–20 TB depending on provider), running coturn on Ubuntu. That's $5/month plus your time.

At a relayed traffic level of 1 TB/month — well within ExpressTURN's free tier — self-hosting is ~$5/month plus the engineering hours. ExpressTURN's free plan is $0. Self-hosting only wins on cost once you outgrow the free tier and don't want to pay $9 for premium.

At AWS/GCP/Azure egress prices (~$0.09/GB), coturn becomes wildly more expensive than ExpressTURN. 1 TB on AWS is ~$90/month in egress before you've added the EC2 cost.

When self-hosted coturn is the right choice

Strict data-locality compliance. Some healthcare, defense, or government deployments require all packets stay inside a specific jurisdiction or on owned infrastructure. Self-host.
Pushing 10+ TB/month relayed. A budget VPS with high bandwidth + a competent ops engineer is genuinely cheaper at this volume.
You enjoy and have time for infra work. Setting up a multi-region coturn cluster with shared-secret auth, GeoDNS routing, and TLS renewal is a fun weekend if that's your thing.
You need on-prem deployment. Air-gapped corporate networks, internal-only applications.

When ExpressTURN is the right choice

You're shipping a product, not infrastructure. Five minutes of signup vs. a week of setup.
You need global low-latency relay. 20+ regions cost essentially nothing on the $9 plan; reproducing that with coturn is a multi-VPS, GeoDNS-routed project.
You're under 5 TB/month relayed. $9 is cheaper than your time.
You don't want to be paged when a TLS cert expires or a VPS provider has an outage.

Hybrid: use both

A surprisingly common pattern: list ExpressTURN and your own coturn instance in the client's iceServers. ICE will pick the best path. You get redundancy and cheap fallback in one move.

iceServers: [
  { urls: 'stun:stun.expressturn.com:3478' },
  { urls: ['turn:relay1.expressturn.com:3478?transport=udp', 'turns:relay1.expressturn.com:443?transport=tcp'],
    username: 'EXPRESS_USER', credential: 'EXPRESS_CRED' },
  { urls: ['turn:turn.your-domain.com:3478?transport=udp'],
    username: 'OWN_USER', credential: 'OWN_CRED' }
]

FAQ

Is coturn free?

The software is free; running it is not. You pay for VPS, bandwidth, and your time.

How long does coturn setup take?

4–8 hours for a single-region first install with TLS, firewall, and validation. Multi-region is a multi-day project.

Does ExpressTURN run coturn under the hood?

ExpressTURN runs a hardened, multi-region TURN deployment. The wire protocol is standard RFC 5766/8656 — your client code doesn't care.

When should I pick self-hosted coturn?

Strict data-locality, very high relayed traffic, on-prem deployment, or you actively enjoy infra work.

Skip the VPS, ship the product.