Support
Need help with ProofAnchor? We're here to assist.
For account issues, billing questions, or general inquiries.
[email protected]We typically respond within 24 hours. Business plan customers receive priority support.
What does ProofAnchor actually prove?
ProofAnchor proves that a specific file existed in your possession at a specific point in time. The SHA-256 hash of your file is anchored to the Polygon blockchain with an immutable timestamp. This proves temporal priority — you had it first.
Does ProofAnchor store my files?
No. Your files are hashed entirely in your browser. Only the cryptographic fingerprint (SHA-256 hash) is sent to our servers and written to the blockchain. We never see, store, or access your actual files.
Can a proof be deleted or modified?
No. Once a hash is anchored to the Polygon blockchain, it is permanent and immutable. No one — not even us — can alter or remove it. This is by design.
How do I verify a proof?
Every proof has a public verification URL. Anyone can visit that URL, drop the original file, and confirm that its hash matches the blockchain record. No account is needed to verify.
How do I cancel my subscription?
Go to Settings and click "Manage Billing" to access the Stripe billing portal. You can cancel, change plans, or update payment methods there. You retain access through the end of your billing period.
What file types are supported?
Any file type — images, audio, video, documents, code, archives, and more. If your computer can read it, ProofAnchor can hash it.