Proof Holdings vs Plivo Verify
Plivo's $0 verification fee is a real edge for US-only, high-volume SMS — and its AI Fraud Shield blocks the SMS-pumping attacks that plague OTP. The fine print: '$0' still means full per-country SMS costs, and you're left holding a status flag.
Proof is structurally immune to SMS pumping — there's nothing to pump when the user sends the code — and the price, from €0.0079 a proof, carries no SMS delivery cost in any country. What you keep is a signed proof, not a line item.
One API · One key
One key does what a stack of vendors does
Every provider on this page delivers codes to phones. Proof is a single API — the same reverse-OTP flow also covers email and domains, and every verification mints a signed, offline-verifiable ES256 token for each of these:
Same price · Any asset
The same price for every asset — phone, email, and domain today, with wallet and social coming soon. No per-seat or per-MAU fees — the meters that make rivals' bills jump.
- Free every month
- 300 proofs
- Pay as you go
- €0.03 / proof
- At volume
- €0.0079 / proof on the €79 plan
Feature Comparison
Swipe to compare →
| Feature | Proof Holdings | Plivo Verify |
|---|---|---|
| Phone verification | Telegram, WhatsApp, SMS | SMS, Voice, WhatsApp |
| Email verification | Magic Link, OTP | No |
| Domain verification | DNS TXT, HTTP, Admin Email, Auto-Verify | No |
| Wallet verification | Coming soon (8 chains planned) | No |
| Social verification | Coming soon (12+ platforms planned) | No |
| Verification fee | From €0.0079/proof (includes everything) | $0 (but you pay full SMS channel costs) |
| Reverse OTP | Yes | No |
| Cryptographic proof tokens | ES256 JWT, offline-verifiable | No |
| Fraud protection | Inherent (user-initiated Reverse OTP) | AI Fraud Shield (SMS pumping detection) |
| HITL approvals | Telegram/WhatsApp with proof tokens | No |
| MCP server | 167 tools | No |
| No code in transit to intercept or phish | Yes | No |
Pricing
Verification fee
Proof Holdings
From €0.0079/proof (no SMS fee)
Plivo Verify
$0 verification fee
Total cost per verification (Europe)
Proof Holdings
From €0.0079 a proof, no SMS fee
Plivo Verify
$0 verification + SMS channel cost ($0.009 US, $0.08 France, varies by country)
Total cost per verification (international)
Proof Holdings
From €0.0079 a proof, same in every country
Plivo Verify
$0 verification + $0.009/SMS (US), $0.08/SMS (France), country-variable
Asset coverage
Proof Holdings
Phone, email, domain — same price (wallet & social soon)
Plivo Verify
Phone only (SMS, Voice, WhatsApp)
The $0 Verification Fee — What It Really Means
Plivo's headline is compelling: $0 verification fee. But this means they don't charge a platform fee — you still pay the full SMS channel cost for every message sent.
SMS costs on Plivo start at $0.0055 per SMS + carrier surcharges ($0.0085-0.0105 total in US) in the US and go much higher internationally — $0.05-0.50+ depending on destination country, plus carrier surcharges on all usage.
Proof Holdings charges from €0.0079 per proof, which includes everything — no separate channel fees, no carrier surcharges, no country-variable rates. For most international use cases, Proof Holdings is significantly less expensive despite having a non-zero verification fee.
Plivo's $0 fee is a marketing distinction, not a cost advantage. The total cost per verification matters, and it's higher on Plivo for most international destinations.
Fraud Protection: Two Approaches
Plivo offers an AI Fraud Shield that detects and blocks SMS pumping fraud (artificially inflated traffic). This is a real problem for SMS-based verification — attackers trigger thousands of OTP messages to premium-rate numbers.
Proof Holdings doesn't need SMS fraud protection because Reverse OTP is inherently fraud-resistant. The user initiates the message, not the service. There's nothing to pump. SMS pumping attacks are structurally impossible with Reverse OTP.
Reliability
Plivo sends SMS or voice OTP to the user. Some SMS codes never arrive — carrier filtering and regulations. Microsoft has reported SMS delivery as low as 50% in some regions, and when India changed its SMS filtering rules in March 2021, OTP failure at leading banks went above 25% (Business Standard).
Proof Holdings uses Reverse OTP: the user sends a message to the service. No code to deliver, since the user initiates the action.
When to use Plivo Verify
- You're doing high-volume US-only phone verification where $0 fee + low US SMS rates is attractive
- You need Plivo's AI Fraud Shield for SMS pumping protection
- You're already in the Plivo ecosystem (voice, SMS)
When to use Proof Holdings
- You verify users internationally (our price, the same in every country, beats their country-variable SMS costs)
- You need more than phone verification (email, domain today; wallet & social soon)
- You want cryptographic proof tokens for every verification
- You want inherent fraud resistance without needing an AI fraud shield
- You want no codes lost in delivery, with Reverse OTP
- You need HITL approvals for AI agents
Frequently Asked Questions
Ready to try Proof Holdings?
300 free proofs per month. No credit card required.
Building with an AI agent? The 167-tool MCP server and test mode let an agent run a real verification right now — machine quickstart in llms-full.txt.
Sources for the SMS delivery figures: Microsoft, “It's Time to Hang Up on Phone Transports for Authentication” (2020-11-10); Business Standard, “SMS scrubbing: Faulty implementation wipes out OTPs, 40% traffic disrupted” (2021-03-09).