CipherSign signs your contracts and legal documents with post-quantum cryptography — entirely on your machine. Get the exact original back from any validated .proof file with built-in extraction. Your documents and signing keys never leave your computer.
Verify imported contacts free, forever · Unlimited signing on every paid plan · No cloud
Get Started in Three Steps
From download to your first signed document.
Install CipherSign on the Microsoft Store for Windows 10 or 11. Find your Machine ID under Settings → License — your license will be tied to this machine.
Choose a plan from Pricing below and click Subscribe Now (secure Stripe checkout, card or PayNow). Then get your license.lic in one of two ways: online from your account in about a minute, or offline by emailing us.
In CipherSign, click Import License (Settings → License) and choose license.lic. Generate your signing identity, export your Contact Card for your recipients, and sign unlimited documents — entirely offline.
What's Free. What Requires a Subscription.
Once you have imported a signer's Contact Card, you can verify their documents forever — at zero cost. Signing, and importing or exporting Contact Cards, require a subscription. The split is per-operation, not per-feature-area.
These work permanently, with or without a subscription.
Each requires an active subscription at the moment of use.
Pricing
Three plans. All include unlimited signing and extraction, Contact Card import and export, every security level, and free verification of imported contacts forever. Licenses are per-machine.
Individual Monthly
Solo professionals · 1 machine
Billed monthly
Individual Annual
Solo professionals · 1 machine
Billed annually
Save 21% vs monthly
Business Annual
Teams · up to 5 machines
Billed annually
5 machines included
license.lic.
Get your license yourself in about a minute — no one has to reply.
license.licFor computers without internet access, or if you prefer email.
license.lic
We reply within 1 business day.
Contact Us
For subscriptions, license transfers, or support — email us directly.
support at cipherplus dot ioTerms of Use — Summary
The full terms appear inside CipherSign on first launch. Below is a plain-language summary of the key points. Last updated: September 29, 2026.
Signing, extracting originals from .proof files, generating or managing signing keys, importing a signer's Contact Card, and exporting your own Contact Card each require a valid license at the moment of use. Verifying contacts you have imported is free forever. The same Sign license unlocks extraction — there is no separate purchase.
You may permanently verify the signatures of every signer whose Contact Card you imported while licensed, whatever your license status afterwards. CIPHERPLUS will not revoke this right. No right is granted to verify signers whose Contact Card you have not imported.
All license purchases are FINAL. No refunds, except that if CIPHERPLUS charges you by mistake or does not deliver a license you paid for, you will receive a full refund.
Each license is personal, may not be transferred to another person, and is bound to a single machine. To move a license to a new machine, email us with your old and new Machine IDs.
Your signing key file is stored only on your machine. If you lose it, CIPHERPLUS cannot recover it and you will be unable to sign new documents as that identity. Documents you signed earlier stay verifiable by anyone who already imported your Contact Card. Back up your key, and share your Contact Card while your license is valid.
You are responsible for verifying the real-world identity of parties whose Contact Cards you import before relying on their signatures.
CipherSign is provided "AS IS" without warranty of any kind. CIPHERPLUS makes no warranties regarding merchantability, fitness for a particular purpose, or non-infringement.
To the maximum extent permitted by applicable law, CIPHERPLUS PTE. LTD. shall not be liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of CipherSign.
You are solely responsible for the documents you sign and their legal and commercial content, and for ensuring your use of CipherSign complies with all applicable laws.
These Terms are governed by the laws of the Republic of Singapore. CipherSign implements NIST FIPS 204 (ML-DSA), validated under NIST CAVP Certificate A7970.