Signing happens on your own machine with NIST-standard post-quantum cryptography. Your documents and your signing key never leave your computer, and anyone who has imported your Contact Card verifies your signatures free, forever.
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. Complete payment on our secure Stripe checkout (card or PayNow). We email you a link straight away to choose who uses each seat: yourself, or anyone you invite by email address. This works the same on every plan.
Open this page in your browser:
cipherplus.io/account →Create an account, confirm the code we email you, click Use a seat myself (or claim the invitation you were sent), then paste your Machine ID and download license.lic — it takes a minute. No internet on that computer? Use the offline way by email instead. Then click Import License in CipherSign (Settings → License), 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.
How CipherSign Protects You
The essentials, in plain terms.
CipherSign uses the new US government (NIST) standard for quantum-safe signatures, and holds NIST CAVP Certificate A7970. Every paid plan includes all security levels.
Your signing key is created on your computer and locked with your password. It is never uploaded, and no one — including us — can read it without your password.
Your signature covers the document together with your name and organisation. If anyone changes even one character of the document afterwards, verification fails.
Signing produces a .proof file that holds your
original document and your signature, so the exact original
can always be taken back out. Others can add their own
signatures to the same .proof.
Sign any type of file. Sign a folder file by file, or as one
zipped .proof — then adding or removing any file
is detected too.
Your licence is a small file tied to this computer. CipherSign checks it on your machine — signing and verifying never need the internet. Automatic online renewal is optional and off by default.
Pricing
Sign and extract any file or folder — offline, quantum-safe.
Every plan is the whole product: unlimited signing and extraction, Contact Card import and export, every security level, and free verification of imported contacts forever. The only difference is how many machines, and how you pay.
Individual Monthly
Solo professionals · 1 machine
Billed monthly
S$19 per machine / month
Individual Annual
Solo professionals · 1 machine
Billed annually
S$15 per machine / month
Save 21% vs monthly
Business Annual
Teams · up to 5 machines
Billed annually
S$11 per machine / month
5 machines included — save 42%
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.