Help Center
Everything you need to know about our Zero-Knowledge verification and how we're building a more transparent review ecosystem.
Frequently Asked Questions
When you upload a digital receipt (.eml), the verification happens locally in your browser. We use DKIM signatures—the same tech that verifies emails are real—to prove the purchase happened. ValidHub only receives a mathematical proof; we never see or store your private receipt data.
Immutability means that once a verified review is posted, it cannot be edited, hidden, or deleted by the business. Unlike legacy platforms that allow brands to pay to hide bad feedback, ValidHub ensures the data is etched in code for a 100% honest track record.
We use a Nullifier system. Every receipt generates a unique cryptographic hash. If someone tries to use the same receipt twice or create multiple accounts with one purchase, the system mathematically blocks it. One real purchase equals one real review.
Yes! We have a Forever Free plan that allows you to claim your profile, manage your product, and invite customers to leave verified reviews. It’s built for founders who want to build trust without legacy platform paywalls.
Never. Users can choose to post Anonymously. Because our verification proves they are a real buyer without needing to reveal their personal email to the business, reviewers can share honest feedback without fear of retaliation.