An encrypted Smash alternative — zero-knowledge
Smash is great for sending large files without a size cap — but, like most transfer services, it can read them. SealFile encrypts your files in the browser so no one but your recipient ever can.
Why look for a Smash alternative?
Smash made its name on one thing: send big files, no size limit. That's a real advantage. But Smash encrypts your files with keys it controls, which means the service can technically open them. For marketing assets or video, that may be fine — for anything confidential, it's a gap.
SealFile takes the privacy-first path. Every file is encrypted in your browser beforeit's uploaded, using AES-256-GCM. The decryption key lives in the link fragment (after the #), which browsers never send to any server. We store only encrypted data we cannot read.
SealFile vs Smash
| Feature | SealFile | Smash |
|---|---|---|
| End-to-end (zero-knowledge) encryption | ||
| Files encrypted in your browser | ||
| Provider cannot read your files | ||
| Password protection | ||
| Custom expiry control | ||
| One-time / download-limited links | Limited | |
| No account required | Limited | |
| Open-source encryption client | ||
| Max file size (free) | 200 MB | No limit |
Comparison reflects each service's free tier. Smash allows larger transfers; SealFile prioritizes zero-knowledge privacy.
What you get with SealFile
Zero-knowledge by default
AES-256-GCM encryption runs in your browser. We only ever store ciphertext we can't decrypt.
The provider can't peek
Unlike transfer services that hold the keys, SealFile never has the means to read your files.
Free password protection
Lock any share behind a password derived with Argon2id — no paid tier required.
Auto-expiring shares
Set an expiry from 1 hour to 30 days, or a download limit. Then the encrypted data is gone.
Frequently asked questions
Is Smash end-to-end or zero-knowledge encrypted?
No. Smash encrypts files in transit and at rest, but it holds the encryption keys — so the service can technically access your files. SealFile uses zero-knowledge encryption: files are encrypted in your browser and the key never reaches our servers.
Smash has no file-size limit — why choose SealFile?
If your priority is moving very large files, Smash's no-limit transfers are genuinely useful. If your priority is privacy — making sure no one, not even the provider, can read what you send — SealFile is the better fit. Pick based on what the file needs.
What's SealFile's file-size limit?
SealFile supports files up to 200 MB each, with up to 5 files per share. We trade raw size for true zero-knowledge privacy.
Do I need an account?
No. SealFile requires no sign-up at all — just drop your files, encrypt, and share the link.
Smash and other product names referenced here are trademarks of their respective owners. SealFile is an independent product and is not affiliated with, endorsed by, or sponsored by Smash. This comparison is based on publicly available information as of June 2026 and may change over time — for the most current details, please check Smash's own website.
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