STUN server list

stuns

# source : http://code.google.com/p/natvpn/source/browse/trunk/stun_server_list
# A list of available STUN server.

stun.l.google.com:19302
stun1.l.google.com:19302
stun2.l.google.com:19302
stun3.l.google.com:19302
stun4.l.google.com:19302
stun01.sipphone.com
stun.ekiga.net
stun.fwdnet.net
stun.ideasip.com
stun.iptel.org
stun.rixtelecom.se
stun.schlund.de
stunserver.org
stun.softjoys.com
stun.voiparound.com
stun.voipbuster.com
stun.voipstunt.com
stun.voxgratia.org
stun.xten.com

stunserver.org is domain-parked, no service I would expect there.

NAT is still an issue with voip.

I maintain a reguarly updated list of STUN servers. You can check it out here: https://github.com/pradt2/always-online-stun

Try this tool for STUN Testing.
https://icetest.atec-systems.com/

New free STUN server.

https://freestun.net/

You can get and use list of public STUN servers from Emercoin: https://github.com/emercoin/emercoin/blob/master/src/gen-stun-list.c

you can also try Open Relay Project for free STUN and TURN servers

STUN:stun.f.haeder.net:3478 is also available. Since I maintain this (including all services, too) in my free-time, please be kind.

stun.cloudflare.com:3478

My udp/tcp/v4/v6 stun server: stun.flashdance.cx:3478

New service https://fastturn.net

To test servers in batch visit https://webrtc.github.io/samples/src/content/peerconnection/trickle-ice/
and paste this

// for testing servers connection batch
var list = `paste lists here`;
list.split('\n').forEach((test) => {url.value = "stun:" + test; addServer()})

or https://icetest.info

var stunlist = `list without prefix stun:`;
const checkUrl = document.getElementById("add-new-stun");
const addBtn = document.querySelector(".btn.btn-outline-primary.btn-block")
stunlist.split('\n').forEach((stun) => {
    checkUrl.value = "stun:" + stun;
    addBtn.click();
})