Frequently Asked Questions

Visit callspoof.org and click "Sign Up Free". Fill in your username, email and password. You'll receive a verification email — click the link to activate your account. The whole process takes under 2 minutes.

Within 5 minutes of creating your account and adding balance, you can be making calls. Simply copy your SIP credentials from the dashboard, enter them into your softphone (Zoiper, MicroSIP, or Bria), and dial.

Any SIP-compatible softphone works with our SIP service. Popular options include Eyebeam, Zoiper (Windows/Mac/Android/iOS), MicroSIP (Windows), Bria (all platforms), Linphone (open source), and Grandstream Wave (mobile). We provide configuration guides for all major softphones.

SIP credentials are the settings you enter into your softphone to connect to our network. They include: SIP Server, Username, Password, and Port. You'll find these in your dashboard under "SIP Settings" after logging in.

Account creation is completely free with no credit card required. To make calls you'll need to add a minimum balance of $30 USD via NOWPayments. There is no free trial period, but you can contact us on WhatsApp or email to discuss your requirements before signing up.

No special hardware is required. All you need is a computer or smartphone with an internet connection and a free softphone app. CallSpoof works entirely over your existing internet connection — no physical phone lines needed.

Per-second billing means you are charged only for the exact number of seconds your call lasts — not rounded up to the nearest minute. A 45-second call costs 45 seconds of airtime, not 60. This typically saves call centers 20–40% compared to per-minute providers.

The minimum balance top-up is $30 USD per transaction. All payments are processed via NOWPayments cryptocurrency payment system. Your balance is activated instantly after payment confirmation.

All payments are processed through NOWPayments, our cryptocurrency payment processor. We accept Bitcoin (BTC), USDT (TRC-20 and ERC-20), Ethereum (ETH), and other major cryptocurrencies. Payments are typically confirmed within minutes.

No. Your balance never expires as long as your account remains active. There are no monthly fees, no idle fees, and no maintenance charges. Your credit stays in your account until you use it.

No monthly fees and no contracts. CallSpoof operates entirely on a prepaid basis — you add balance when you need it and pay only for what you use. Cancel anytime with no penalties.

Refund requests must be submitted within 24 hours of the charge via WhatsApp or email. Each case is reviewed individually. Approved refunds are processed within 14 business days. See our Terms & Conditions for full details.

We support G.711u (PCMU), G.711a (PCMA), G.729, and Opus codecs. For best call quality we recommend G.711u or Opus. For bandwidth-constrained connections, G.729 provides good quality at lower bandwidth usage.

SIP signaling uses port 5060 (UDP) or 5061 (TLS/SIPS). RTP media streams use ports 10000–20000 (UDP). Ensure these ports are open on your firewall. If you experience one-way audio, a NAT traversal issue is usually the cause.

One-way audio is almost always a NAT traversal issue. Try enabling STUN in your softphone settings (use stun.callspoof.org), enable "Use rport" and "Symmetric RTP" if available, or configure your router to forward RTP ports 10000–20000. Contact support on WhatsApp or email if the issue persists.

In Zoiper: Settings → Accounts → Add Account → SIP. Enter your SIP server (from your dashboard), username, and password. Set the codec to G.711u and enable STUN. Save and wait for the green registration indicator.

Each VoIP call requires approximately 85–100 kbps using G.711, or 32 kbps using G.729. A standard broadband connection (10 Mbps+) can easily handle dozens of simultaneous calls. Low latency (<150ms) and stable connection are more important than raw speed.

Yes. There is no hard limit on simultaneous calls — it depends on your account balance, internet bandwidth, and the capacity of your softphone or PBX. Call centers running hundreds of concurrent calls are common on our platform.