Trust,
without permission.

Production timestamps and signatures, with open ZK proof infrastructure and explicit feature readiness.

Timestamp a file Self-host in 60s How it works

Local-first records. Anchored on Bitcoin.
Independently verifiable outcomes.

01

Timestamp

Create a verifiable record that a file, hash, or text existed at a specific point in time.

Open timestamp Local SHA-256 · Bitcoin via OTS
02

Proof lab

Generate self-attested age or income range proofs locally and inspect their public signals.

Open proof lab Groth16 · Ceremony pending
03

Sign

Create a signing request, bind signers to a document hash, and track the audit trail.

Open sign Ed25519 · Audit trail
04

Auth preview

Review the issuer-bound partner Auth contract. Production challenges are currently disabled.

Review Auth Issuer required · Fail closed
  1. 01 Hash

    Hash files and signing inputs locally.

  2. 02 Sign

    Bind records with signatures or commitments.

  3. 03 Anchor

    Anchor records externally for durability.

  4. 04 Prove

    Verify later without accounts or permission.

Built on principles

Trust is
earned by design.

OTRUST exists to make digital truth verifiable without permission, accounts or intermediaries.

Local-first

Hashing and sensitive checks run in your browser where possible.

Zero-knowledge

Timestamping never needs your file contents.

Immutable

Anchored in the Bitcoin blockchain via OpenTimestamps.

Open source

Transparent by default. Verifiable by everyone.

05

What you get

Output
Verifiable record
Created by
Timestamp, ID, Sign or Auth
Record ID
a3f2bde6fc7d9e1b3a6c8d2e4f6a1b7c9d0e2f1…
Timestamp (UTC)
May 24, 2025 — 14:32:18
Signature
ed25519:7f31a1c…e9b2

Save the record ID to verify later.

How records verify
Local-first record workspace

Timestamp, verify and manage records.

Hash locally, sign with your browser key, anchor externally, and keep every receipt independently verifiable.

SHA-256 local hash Ed25519 signature Bitcoin anchoring via OTS
01 / Hash and sign

Timestamp files

Drop one or many files. Only hashes and record metadata leave the browser.

Drop files here or browse Hashed locally - never uploaded
Automatic alert in ~1–2 hours. Email is deleted after sending.