SIP Softphone — Open Source

Your PBX.
On your desktop.

Make and receive calls on any SIP-compatible VoIP system. No subscription. No cloud dependency. Built in Go.

Download Free See Features →
k-phone
Main Account
Registered
Extensions
Front Desk
101
Support
102
Sales
103
Management
100
Dial
History
Answering Machine
+49 221 ·····
1
2
3
4
5
6
7
8
9
*
0
#
Call
01 — Features

Everything a professional
softphone needs.

Built from scratch in Go — no native SIP libraries, no runtime dependencies. A single binary that just works.

Full SIP Stack

REGISTER, INVITE, BYE, CANCEL, OPTIONS, MESSAGE, DTMF, Blind Transfer, and BLF — pure Go, zero native libraries.

Secure Transports

Connect over UDP, TCP, TLS, WebSocket or WSS. Choose the transport that fits your VoIP infrastructure.

HD Audio

G.711 PCMU/PCMA plus G.722 wideband for crystal-clear voice calls. Each call shows the negotiated codec.

Busy Lamp Field

Live presence panel for any number of extensions. Green/yellow/red dots update in real-time. Click to dial.

Call Controls

Hold/Resume, mute, blind transfer, DTMF tones — complete in-call management with per-call audio routing.

Native Performance

Single self-contained binary built with Go and Wails — fast startup, minimal RAM, no runtime dependencies.

02 — Calling

A dialpad that stays
out of the way.

Dial any SIP extension or PSTN number, see BLF at a glance, and transfer with a single click.

  • Real-time BLF presence for all extensions
  • Click-to-dial from the extension panel
  • Hold, mute, and blind transfer in one click
  • Full call history with caller ID and timestamps
Download now →
k-phone — In Call
Main Account
Registered
Extensions
Front Desk
101
Support
102
Sales
103
Dial
History
+49 221 123456
● Connected · 02:47 · G.722
Mute
Hold
Transfer
End Call
k-phone — Answering Machine
Greetings
Office Hours
Good day, please leave a message…
Active
After Hours
We are currently closed…
Messages (3 new)
+49 30 987654
0:42
+49 221 111222
1:13
Unknown
0:08
03 — Answering Machine

Never miss a call
when you're away.

Built-in answering machine with named greetings, automatic call recording, and an animated ribbon that shows when it's live.

  • Multiple named greetings — switch with one click
  • Preview greetings through your local speaker
  • Animated ribbon indicates active recording
  • Messages listed with caller ID and duration
Download now →
04 — Download

Free. No account needed.

Self-contained binaries for Linux and Windows. Download, run, enter your SIP credentials — done.

Linux
Linux
AppImage · x86-64
Download for Linux
Requires FUSE or Linux kernel 5.13+
Windows
Portable EXE · x86-64
Download for Windows
No installation required
05 — Getting Started

Up and running
in under a minute.

No installer wizard. No package manager. Download, run, connect.

Linux (AppImage)

  1. Download k-phone-linux-amd64.AppImage
  2. Make it executable and run it — no root access needed
  3. Open Settings, enter your SIP details, click Save & reconnect
chmod +x k-phone-linux-amd64.AppImage ./k-phone-linux-amd64.AppImage

Windows (Portable)

  1. Download k-phone-windows-amd64.exe
  2. Double-click to launch — no installer, no UAC prompt
  3. Open Settings, enter your SIP account details, and click Save & reconnect