CipherSign signs your contracts and legal documents with post-quantum cryptography — entirely on your machine. Your documents and signing keys never leave your computer.
Verification free forever · Unlimited signing on every paid plan · No cloud
Get Started in Three Steps
From download to your first signed document.
Install on Windows 10 or 11. Verification works immediately — free, no account needed. Find your Machine ID under Settings → License.
Choose a plan from Pricing below and click Subscribe Now. Complete payment on our secure Stripe checkout (card or PayNow). Then email your Stripe receipt + Machine ID to [email protected] — we reply with your license.lic within 1 business day.
Open license.lic in CipherSign (Settings → License → Browse), generate your signing identity, and sign unlimited documents — entirely offline.
What's Free. What Requires a Subscription.
Anyone can verify a signed document forever — at zero cost. Signing requires 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, all three ML-DSA security levels, and recipients verifying free 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 file within 1 business day.
Contact Us
For transfers and support. To start a new subscription, use the Subscribe Now button on any plan in Pricing above.
Move a license to a new machine. Include both old and new Machine IDs.
Email: Transfer LicenseOr email us directly
andy 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: April 2026.
Verification is free forever and never requires a license. Signing, generating signing keys, renaming signing keys, and exporting Contact Cards each require an active subscription at the moment of use.
The right to verify documents signed with CipherSign is granted to all users permanently and unconditionally, regardless of license status. This right cannot be revoked.
All license purchases are FINAL. No refunds, exchanges, or money-back guarantees. Verify CipherSign works for you using the free verification feature before subscribing.
Each license is personal, non-transferable, and 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. Previously signed documents remain verifiable forever. Back it up.
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.