Both services send secrets that destroy themselves after the first retrieval. The difference lies in who holds the key, and in whether you can also ask someone for a credential instead of only sending one. Both sides are here, including the points where OneTimeSecret is ahead.
In short: OneTimeSecret has been around far longer, it is better known, and for simply sending a one-time link it is entirely sufficient. Erseni Vault differs on two points that may count for you: the server never sees the plaintext, because encryption and decryption happen in the browser, and you can request credentials from one specific person instead of only sending them.
Every line states what each tool does, not just a tick or a cross. Where we are behind, it says so.
Your team already knows and uses the service. Switching costs adjustment, and for simply sending a one-time link it gains you little.
You want a permanent drop-off page under your own domain where people can keep leaving things for you. Incoming Secrets are built for exactly that.
Server-side encryption is enough for you, and you would rather have a service with many years of operation behind it.
The usual sequence takes the problem the wrong way round. You need a password that somebody else holds, so you ask for it by email, and the answer comes back in plaintext by email. One-time-link services do not solve that case: they help whoever is sending something, not whoever needs something. With Erseni Vault you create a request link and send it to the person. Their browser generates a key pair locally, encrypts what they type against it and sends us nothing but ciphertext. You alone can decrypt it. They need no account, no software and no understanding beyond filling in a field.
We compare against public documentation and source code, and we say when we have not verified something ourselves. Products change: if a detail here matters to your decision, check it at the source before you rely on it.
OneTimeSecret on GitHub Release 0.26.0 of 19 July 2026 shipped Incoming Secrets. For the server-side encryption we follow the description given by the project; we have not measured it in the source code ourselves.
Incoming Secrets documentation Describes the drop-off page on a verified custom domain. The page still carries a notice that it is a work in progress.
Erseni Vault source code The cryptography component behind both sending and requesting, readable under the AGPL.
Send a secret or create a request link right now, without an account. The comparison above is easier to judge once you have used both.
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