Proof Holdings vs Vonage Verify
Vonage Verify earns its place — Silent Network Authentication confirms a number at the carrier level with zero taps, elegant where coverage reaches. What's left in your hands afterward is the question: a platform fee, per-country SMS charges, and a status flag that evaporates. Same job with Proof; you keep the proof.
Vonage sells delivery; Proof removes the need for it — the user sends the message, so no code can fail to arrive. From €0.0079 a proof, the same in every country, and a signed token that outlives the session: that's why teams verifying international users pick Proof.
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 | Vonage Verify |
|---|---|---|
| Phone verification | Telegram, WhatsApp, SMS | SMS, Voice, Silent Auth, WhatsApp |
| Email verification | Magic Link, OTP | OTP |
| 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 |
| Reverse OTP | Yes | No |
| Cryptographic proof tokens | ES256 JWT, offline-verifiable | No |
| Human-in-the-loop approvals | Telegram/WhatsApp with proof tokens | No |
| MCP server for AI agents | 167 tools | No |
| Code delivery | No code to deliver (user sends it) | SMS codes can fail to arrive |
| No code in transit to intercept or phish | Yes | No |
| Silent Network Auth | No | Yes |
| Free tier | 300 proofs/month | No |
Pricing
Platform fee per verification
Proof Holdings
€0.0079/proof (€79 plan, any asset)
Vonage Verify
$0.057/verification (platform fee only)
Total cost (phone SMS, Europe)
Proof Holdings
From €0.0079 a proof, no SMS fee
Vonage Verify
$0.057 + SMS channel fee (€0.05-0.10+ per SMS)
Free tier
Proof Holdings
300 proofs/month
Vonage Verify
No free tier
Multi-asset pricing
Proof Holdings
Same price, from €0.0079, for phone, email, domain (wallet & social soon)
Vonage Verify
Phone and email only — no domain, wallet, or social
Reliability
Vonage Verify sends an SMS or voice call to the user. Like all SMS-based verification, some codes never arrive — carrier filtering, number portability and regional rules; Microsoft has reported SMS delivery as low as 50% in some regions.
Proof Holdings uses Reverse OTP: the user sends a message to the service via Telegram, WhatsApp, or SMS. Since the user initiates the message, no code has to reach the user, so none can be lost on the way.
Vonage offers Silent Network Authentication as an alternative — carrier-level verification with zero user interaction. This works well where carrier partnerships exist but has limited global coverage and doesn't work on WiFi.
0
Codes sent to the user (Proof)
50%
Lowest SMS delivery rate Microsoft reported for some regions
10
Live verification channels (Proof)
True Cost Comparison
Vonage's pricing has two layers: a $0.057 platform fee per successful verification, plus SMS channel fees that vary by country. In Europe, SMS costs can add €0.05-0.10+ per message. Total cost per phone verification in Europe: $0.10-0.16+.
Proof Holdings charges €0.0079 per proof on the €79 plan. This covers phone, email, or domain — wallet and social coming soon. No additional channel fees. The price is the price.
For 10,000 phone verifications in Europe, Vonage costs approximately $1,000-1,600+. Proof Holdings costs €79 (the €79 plan includes 10,000 proofs).
Security
SIM-swap attacks compromise SMS-based verification. Vonage Verify's SMS and voice channels are vulnerable to this attack vector. Their Silent Auth avoids it but has limited coverage.
Reverse OTP sends no code to intercept or phish, and on Telegram and WhatsApp a SIM swap alone is not enough — the attacker must also take over the messaging account, which two-step verification blocks when the user has turned it on.
Every verification produces an ES256-signed JWT proof token verifiable offline. Vonage returns a status flag with no cryptographic attestation.
When to use Vonage Verify
- You need Silent Network Authentication (carrier-level, zero-interaction verification)
- You want an enterprise CPaaS platform with voice, video, and SMS in one suite
- Your use case is strictly phone verification in markets with good carrier coverage
- You need the Vonage ecosystem (Programmable Voice, Video API, etc.)
When to use Proof Holdings
- You need to verify more than phone numbers (domain today; wallet & social coming soon)
- You want cryptographic proof tokens for every verification
- You operate internationally where SMS delivery is unreliable
- You need human-in-the-loop approvals for AI agents
- You want predictable, all-in pricing without channel surcharges
- You want all-in pricing that doesn't move with the destination country — one rate for any asset
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).