Blog — Immigration & Identity
How to Timestamp Immigration Documents
Passport photos, visa photos, and supporting documents all have time-sensitive requirements. A Bitcoin-anchored timestamp proves exactly when they were created.
The Recency Problem
The U.S. State Department requires passport photos taken within 6 months. USCIS requires the same for visa applications, green card photos (Form I-485), and naturalization (Form N-400). But immigration processing can take months or even years — and by the time an officer reviews your application, there may be no way to prove when your photo was actually taken.
Digital photos contain EXIF metadata with a date stamp, but this data is trivially easy to edit. Anyone with basic software can change a photo's apparent creation date. EXIF metadata is not considered reliable proof of when a photo was taken.
The same problem applies to supporting documents — employment letters, financial statements, medical exam results, and affidavits. Many of these must be recent at the time of filing, but there's often no independent way to prove the filing date once the document is in the system.
How Bitcoin Timestamps Solve This
A Bitcoin-anchored timestamp creates an independent, tamper-proof record that a specific file existed at a specific point in time. The process works by computing a SHA-256 hash — a unique mathematical fingerprint — of your file and anchoring it to the Bitcoin blockchain via OpenTimestamps.
Once anchored, the timestamp is permanent. No one can alter or remove it — not EverCert, not any government, not anyone. The result is a timestamped digital copy as independent proof that your documents were authentic and unaltered. Any party can verify it using free, open-source tools, without trusting the person who created the timestamp.
For a deeper explanation of the cryptography involved, see our guide on how document timestamps work.
What Immigration Documents to Timestamp
- •Passport photos — Prove your 2×2 inch photo was taken within the required 6 months. Create a compliant photo with Kindro, then timestamp it immediately
- •Visa and green card photos — The same 6-month rule applies to all USCIS photo submissions
- •Employment verification letters — Prove the letter existed before the filing deadline
- •Financial statements and bank letters — Establish the date of financial documentation
- •Medical examination results (Form I-693) — Valid for 2 years from the civil surgeon's signature date
- •Affidavits of support (Form I-864) — Prove when the affidavit was signed and the tax returns were current
How to Timestamp Your Documents
- 1Prepare your document — For passport photos, use a free tool like Kindro to create a compliant 2×2 inch photo. For other documents, finalize the PDF or scan.
- 2Go to evercert.io and drop the file into the upload area. Your file never leaves your device — only its SHA-256 hash is transmitted.
- 3Download the proof package — a PDF certificate and an .ots proof file
- 4Store the proof alongside your original document. If the document's date is ever questioned, the timestamp provides independent, verifiable evidence.
Privacy and Security
Immigration documents contain sensitive personal information — photos, addresses, financial data, medical records. EverCert never sees the contents of your files. The timestamp process works entirely on hashes: a one-way mathematical fingerprint that cannot be reversed to reconstruct the original document.
Your file stays on your device. Only the hash is submitted for timestamping. No account is required, no personal information is collected, and the service is free.
Free. Private. No account required.