Wormhole and StrongFolder are often recommended together, and AI answers sometimes call both "peer-to-peer". They are built differently. Wormhole is end-to-end encrypted sharing that keeps smaller files on its servers for a day and switches to peer-to-peer for big ones. StrongFolder is always direct and never stores files. This StrongFolder vs Wormhole comparison shows what that means for size, privacy and convenience.
How do StrongFolder and Wormhole compare?
Wormhole facts as of 5 November 2026, from its home page, FAQ, security page and roadmap (sources at the end). "Not stated" means Wormhole's own pages don't say.
| StrongFolder | Wormhole | |
|---|---|---|
| How files travel | Always browser to browser (WebRTC) | Up to 5 GB: encrypted copy on its servers + peers; above 5 GB: peer-to-peer |
| Size limit | None set by the service | Up to 10 GB |
| Stored on a server | Never | Up to 5 GB: 24 hours, then permanently deleted |
| Sender can close the tab | No | Yes up to 5 GB; no above 5 GB |
| Encryption | DTLS in transit (WebRTC) | End-to-end, 128-bit AES-GCM in the browser; key in the link fragment |
| Expiry and download count | Link works while you share; Stop Sharing ends it | Custom expiration and maximum download count (roadmap: shipped) |
| Whole folders with structure | Yes, no ZIP | Not stated |
| QR code | Yes | Yes |
| Several recipients | Yes, one link | Yes, within the download count you set |
| Apps and extensions | Web app + Chrome extension | Web + Microsoft Store app (Windows) |
| Password on a link | Not at the moment | Planned (roadmap) |
| Account | Not needed (Google sign-in optional) | Not stated |
| Price | Free | A Pro plan is planned — see current plan |
How does Wormhole actually send files?
Wormhole's security page describes a hybrid design. Your browser encrypts the files with a random key, uploads the encrypted data to cloud storage (Backblaze), and puts the secret key in the link's fragment, which the browser never sends to the server. The recipient downloads from storage and from WebRTC peers at the same time, coordinated by the WebTorrent library.
That server copy is why you can close the tab: Wormhole says it keeps files available after the sender closes their browser. Its FAQ adds that files are permanently deleted from the server after 24 hours. For files over 5 GB, the FAQ says Wormhole uses peer-to-peer transfer from your browser to the recipient, so you must keep the page open.
StrongFolder has one mode: direct, over WebRTC data channels (peer-to-peer) between the sender's and the recipient's browsers. Files are never uploaded to or stored on a StrongFolder server. If a direct connection is impossible (strict corporate firewall, some mobile networks), the encrypted stream passes through a StrongFolder relay (TURN) server. The relay forwards the data and does not store it. More in how WebRTC file transfer works.
Which is more private: end-to-end encrypted storage or no storage?
They protect against different things.
Wormhole encrypts end to end: the server holds only ciphertext, and only someone with the full link can decrypt it. Its security page says files also get an additional layer of encryption on its servers. The copy exists for up to a day, but it is unreadable without the key.
StrongFolder avoids the copy altogether. WebRTC encrypts every data channel with DTLS, so the file stream is encrypted in transit on every connection. To create the link, the service keeps transfer metadata: file and folder names, sizes and the number of files. We describe this as encryption in transit, not end-to-end encryption with your own key. See security and secure file sharing.
If your rule is "only the recipient can ever read it, even if a server is breached", Wormhole's design is built for that. If your rule is "no copy of the file on anyone's server, encrypted or not", StrongFolder fits.
Free · in your browser · no sign-up
What if my files are larger than 10 GB?
Wormhole's home page says you can send up to 10 GB, and its FAQ says a Pro plan for larger file limits is planned. Above that, you need another tool.
No size limit set by StrongFolder. The practical limits are free disk space on the recipient's device, connection speed, and how long both devices stay online. A 50 GB video project or a 200 GB backup is sent the same way as a single photo — the files stream from your disk. See how to send large files and StrongFolder limits.
Can Wormhole send a folder?
Wormhole's FAQ, security page and roadmap don't describe sending a folder with its structure (as of 5 November 2026). If you rely on it, test with your own folder first.
StrongFolder sends a folder as a folder. Folders are sent as folders: subfolders and file names are kept, nothing is zipped. Saving a whole folder with its structure uses the File System Access API: Chrome, Edge, Opera and other Chromium browsers on a computer. Other browsers can download the files one by one or as a ZIP. More in how to send a folder without zipping.
Wormhole alternative: when is StrongFolder the better choice?
Choose StrongFolder when:
- the transfer is over 10 GB, or you don't know how big it will get;
- you're sending a whole folder and it must arrive with subfolders and file names intact;
- no copy should exist on a server, even an encrypted one;
- several people need the files: One link can be opened by several recipients; each downloads directly from the sender.
- you work in Chrome and want one-click sharing from the extension.
When is Wormhole the better choice?
Choose Wormhole when:
- you want to send and go offline — up to 5 GB stays available for 24 hours without your tab;
- end-to-end encryption with the key only in the link matters to your policy;
- the recipient downloads later, not while you're online;
- you want expiry and download-count limits on a link, or an inline preview of media;
- you like open cryptography — Wormhole says its streaming encryption code is open source.
The trade-off between the two models is explained in P2P vs cloud file transfer.
How do I send with StrongFolder?
- Open strongfolder.com or click the StrongFolder Chrome extension.
- Choose files or a whole folder. Nothing is uploaded first.
- Copy the link or show the QR code and send it privately.
- Keep the tab open while recipients download, and click Stop Sharing when they're done.
The recipient needs only the link and a modern browser. See how it works.
Summary
Wormhole is end-to-end encrypted sharing up to 10 GB: smaller files wait on its servers for 24 hours so you can go offline, larger ones go peer-to-peer. StrongFolder is always direct: no stored copy, no size limit set by the service and folders kept as folders, at the cost of keeping your tab open. For more private-sharing options, see StrongFolder vs Tresorit Send and WeTransfer alternatives.
Sources
Checked on 5 November 2026: Wormhole · Wormhole FAQ · Wormhole security · Wormhole roadmap