Short answer: Emailing yourself shows an email provider received a message at a time; Git dates show what the committer’s computer said; a notary confirms who signed or that a copy matches, on a date; and a blockchain timestamp shows that an exact file existed no later than a recorded time and still matches its fingerprint, checkable by anyone. None of them proves who created the work. They answer different questions, so many people use more than one.
Disclosure: I’m Inna Hall, co-founder of TimeBinder, the file timestamping tool this guide uses. This page is general information, not legal advice.
Table of Contents
Side by side
| Method | What it shows | Main weakness | Read more |
|---|---|---|---|
| Emailing yourself | An email provider received a message at a time | Date sits with one provider; hard to tie to the exact file later | Emailing yourself as proof |
| Git commit dates | What the committer’s clock said when a commit was made | Dates are set by the committer and can be backdated | Git commit dates as proof |
| Notary or JP | Who signed, or that a copy matches an original, on a date | Covers a paper or copy seen that day; costs per visit | Blockchain timestamp vs notary |
| Blockchain timestamp | An exact file existed no later than a recorded time and still matches its fingerprint | Doesn’t show who made it; only covers files you sealed | TimeBinder vs OpenTimestamps |
Each comparison page goes into detail; this page is the short version. For the full list, see all comparisons.
Start with the question you need answered
- “When did this exact file exist?” A timestamp answers this most directly. Anyone can re-hash the file and compare it with the record.
- “Who signed this, and was it really them?” That is a notary’s job.
- “What did I send, and to whom?” Emails and submission receipts help, because other people hold them.
- “How did this code develop?” Git history shows the sequence of changes; anchoring commits adds outside dates.
If you are weighing older habits, see the poor man’s copyright alternative and RFC 3161 vs blockchain timestamps.
Using them together
These methods aren’t rivals. A writer might email a draft to an editor, keep version history, and timestamp each milestone. A developer might keep Git history and anchor each release. What matters is that the records agree with each other and that at least one of them doesn’t depend on your own computer or account.
Prove your draft history. Seal each draft, note and manuscript as you go, so you can show when every version existed. See how it works →
Files are hashed locally on your computer and are never uploaded.
What a timestamp does and doesn’t do
TimeBinder anchors each file’s SHA-256 fingerprint to Bitcoin and gives you a Proof of Time Certificate. That is verifiable evidence of when a file existed: it shows the file existed no later than the anchor date, and any later change to the file is detectable. ASAP TimeBinds can be checked independently; Pooled TimeBinds are verified through TimeBinder. Your file is hashed in your browser and never uploaded.
It doesn’t show who made the work or who owns it, it doesn’t stop copying, and it doesn’t cover a version you didn’t timestamp. A timestamp is one strong piece of a record, alongside the others above.
Frequently Asked Questions
Which method is best for proving when a file existed?
For the narrow question of when an exact file existed, an independent timestamp is the most direct, because anyone can re-check the file against the record. For identity or signatures, a notary does a job a timestamp can’t.
Is emailing yourself worthless?
No. It is free and better than nothing, especially if the email went to someone else too. Its weakness is that the date depends on one provider’s records and is hard to tie to an exact attachment later.
Can Git commit dates be changed?
Yes. The author and committer dates are set by the person committing and can be backdated. Anchoring a commit hash or a release archive with a timestamp gives an outside date you can check.
Does any of these prove authorship?
No. Each shows something about timing or identity, not who created a work. Authorship is usually shown by the whole picture: drafts, files, messages and agreements.
Plan details were checked against timebinder.io/pricing on 29 October 2026.
