Check a file
Always free
$0no account, no credit
Verify a file against a proof you already hold.
- Drop a file or paste a SHA-256 digest
- No sign-up and nothing to install
- Checking does not spend a credit
◈ Pricing
Checking is free.Anchoring is one-time.
No subscriptions. Buy one-time credit packs and use them whenever you need — credits never expire.
View credit packsChoose how to use Quantum Notary
What you get
A record you can check.
Fingerprint + receipt
Your file stays on your device. Its fingerprint is recorded on Base.
- Transaction details saved in your receipt
- Proof PDF for finalized records
- Compare the record with your original file
Open an account
Credits
$0.16per anchor, at 500 credits
One-time packs. Credits never expire and there is no subscription.
- Records list with search, filters, sort and pagination
- Down to $0.16 per anchor at 500 credits
▸ Credit packs
Buy more at once, pay less per anchor.
One-time payment · tax included
$14.99
50 credits · $0.30 per anchor
save 66%
against buying one credit at a time- Anchors included
- 50
- Price per anchor
- $0.30/ea
- Expiry
- never
- Subscription
- none
- Verifying a file
- free
Price per anchor
From $0.89 at one credit down to $0.16 at 500 — an 82% drop.
Record capacity
Space for your proof history.
Included to start. Expand when you need to.
Every account
10,000 records included
For your fingerprints, receipts and proof history.
Your original files stay with you.
Optional expansion
+10,000 more records
Expansions stack. Notarization credits are purchased separately.
$49 USD · paid once · tax included
Proof records kept for the lifetime of Quantum Notary. No scheduled expiry.
Storage & retention FAQ
Do you store my original files?
Record capacity covers fingerprints, receipts and proof history. When you notarize a file in your browser, it is hashed on your device; we receive its fingerprint and selected metadata, not its contents. Keep your original file for future verification.
How long are records kept?
Lifetime records: no scheduled expiry. We keep proof records for the lifetime of Quantum Notary and do not support record deletion.
Keep your original file and export your proofs for independent verification. That still requires suitable historical Base access if the service stops operating.
Why can’t I delete records to free up space?
A proof may be referenced years after it is created. Keeping its record and proof history preserves the context behind those future checks. That is why we do not support deleting records to reclaim capacity, including after refunds or account closure. A fingerprint already recorded on Base cannot be removed by us or by you.
Personal-data rights are covered separately in our Privacy Notice.
What happens when I reach my record limit?
You need more capacity before adding new records. Your existing records and otherwise authorized proofs remain available. Each expansion adds 10,000 record spaces; expansions stack and have no monthly reset or scheduled expiry. They add no notarization credits.
◇ FAQ
Questions about paying.
Do credits expire?
No. Credits you buy never expire and there's no overage to worry about — when you run out, buy another pack whenever you need to.
Do I need to know cryptography or blockchain?
No. Drop a file or paste its hash in your dashboard — we handle the hashing, the chain submission, and the receipt. No coding required.
Is my file uploaded to you?
The browser hashes exact file bytes locally without uploading the file body. Notarization sends the fingerprint plus filename, byte size and available type. Metadata stays off-chain. The fingerprint is public: predictable inputs can be tested against it, and a shared transaction reveals submission in the same short window.
What if Quantum Notary disappears?
A verifier can recompute the digest and inspect the referenced Base transaction without our API or database. That path still requires the retained input, processing rule, and receipt, and suitable historical Base access.