- Open-source SIP softphone based on the PJSIP stack
- Extremely lightweight footprint (<2.5MB) and low RAM usage
- High-quality voice codecs including Opus, G.711, G.722, G.729, and more
- Video calling with H.264, H.263+, and VP8 support
- SIMPLE instant messaging and presence support
- DTMF support via In-band, RFC2833, and SIP-INFO
- Encryption with TLS and SRTP for secure calls
- STUN, ICE, and NAT traversal compatibility
- Portable configuration using INI files with no external dependencies
- Multi-language and RTL support, accessible with screen readers
MicroSIP
Lightweight open-source SIP softphone for high-quality Windows VoIP calling
Updated February 27, 2026
MicroSIP Overview
MicroSIP is a free, open-source SIP softphone for Windows built on the PJSIP stack. It enables high-quality voice and video calls using open SIP standards, making it compatible with hundreds of VoIP providers worldwide.
Designed for minimal system resource usage, MicroSIP delivers excellent audio quality, strong codec support, encryption options, and a simple, user-friendly interface suitable for both personal and professional use.
Key Features
Pricing
| Plan | Price |
|---|---|
| Open Source (GNU GPL v2) | $0 (Free to Use) |
Pros
Competitor |
Pros |
|---|---|
| Zoiper | Compared to Zoiper, MicroSIP is completely free and open source, with no feature paywalls. It has a significantly smaller footprint and lower RAM usage, making it ideal for older or resource-constrained Windows systems. Its SIP standards compliance and broad codec support also appeal to technically oriented users. |
| Linphone | MicroSIP is easier to deploy on Windows than Linphone, requiring no additional frameworks or dependencies. Its portable design and INI-based configuration simplify setup and troubleshooting. For users focused on Windows-only VoIP calling, MicroSIP offers a more lightweight and straightforward daily experience. |
| Bria | Against Bria, MicroSIP stands out on price, being entirely free versus Bria’s subscription model. It consumes far fewer system resources and avoids licensing management. For users who only need core SIP calling, codecs, and encryption without enterprise extras, MicroSIP is more cost-effective. |
| 3CX Softphone | MicroSIP does not lock users into a specific PBX ecosystem like 3CX. It works with virtually any SIP provider, offering greater flexibility. Its minimal interface and open configuration suit power users who want full control without background services or vendor-specific integrations. |
| RingCentral Softphone | Compared to RingCentral’s softphone, MicroSIP excels in simplicity and cost. It has no recurring fees and runs independently of a unified communications suite. This makes it attractive for individuals and small teams needing reliable SIP calling without bundled collaboration features. |
Cons
Competitor |
Cons |
|---|---|
| Zoiper | Unlike Zoiper, MicroSIP lacks a polished cross-platform experience and official mobile apps. Zoiper offers commercial support and advanced features like call recording and push notifications on mobile, which may be important for business users needing consistent functionality across devices. |
| Linphone | Compared to Linphone, MicroSIP is limited to Windows and does not support Linux or macOS natively. Linphone also provides stronger end-to-end encryption options and a broader roadmap for secure communications, which may matter for privacy-focused organizations. |
| Bria | MicroSIP lacks the enterprise-grade features found in Bria, such as centralized user management, CRM integrations, and professional customer support. Businesses that require guaranteed SLAs, regular UX updates, and advanced collaboration tools may find MicroSIP too basic. |
| 3CX Softphone | When compared to 3CX Softphone, MicroSIP offers no built-in PBX, team collaboration, or call center features. Organizations seeking an all-in-one telephony platform with queues, analytics, and web management will need additional infrastructure alongside MicroSIP. |
| RingCentral Softphone | MicroSIP cannot match RingCentral’s unified communications capabilities, such as team messaging, video meetings, and enterprise integrations. It also relies on community-based support rather than dedicated customer service, which can be a drawback for mission-critical deployments. |
Reviews
- Reddit r/VOIP: MicroSIP “fills the bill exactly” for several commenters who value that it is “truly free, open source,” supports “lots of codecs,” and includes SIPP and SRTP. One user relies on it daily and “love[s] it,” while another highlights the auto call recording feature that removes the need to take “furious notes” during customer calls. A minor gripe mentions a half‑second delay when dialing the first digit.
- G2 Review (Rating: 4.2/5): MicroSIP earns praise for its ease of use, clear sound quality, and lightweight design that enables quick setup. Several reviewers note that it integrates smoothly into existing workflows, though some report occasional connection issues when pairing it with third-party devices.
- Capterra Review (Rating: 4.3/5): Long-term users call it lightweight, free, and backed by “excellent documentation,” with good sound quality and easy call log control for daily call center work. One reviewer values the video conferencing feature and credits it with supporting company growth over six years. Others criticize a “terrible” interface that “looks like a calculator,” describe setup as very hard, and mention trouble with some microphones and reaching customer support.
- softphone.pro Review: The comparison labels it “free, light and simple to minimal,” with a tiny installer footprint of “8 / 5 Mb” and good BLF indication and notifications. The write‑up notes that CRM and web service integration requires extra effort, offers no MS Excel or Google Sheets integration, and does not provide the “20+ reports” highlighted in the competing product.
