I've been putting off writing about this for about a week now because I wanted to actually use the thing before I told anyone to bother with it. Mozilla properly launched Firefox Send out of testing on March 12th, and after using it for basically every big-file transfer since, I think it's quietly one of the better small releases this year.
Here's the problem it solves, in case you haven't hit it yet: someone asks you for a file that's too big to email. Maybe it's a 200MB video export, maybe it's a folder of RAW photos zipped up, maybe it's a client asking for "just the raw data please" and the raw data is 600 megabytes of CSVs. Gmail caps you at 25MB. Most work email systems cap you lower than that and don't even tell you why the send failed, they just silently eat it. So you end up on WeTransfer, which I've always found a bit gross, honestly. Free tier throttles you, nags you about the paid version constantly, and I never fully trusted what happens to a file sitting on their servers for a week.
Send is different in a few ways that actually matter. It encrypts the file in your browser before it ever leaves your machine, so Mozilla's servers only ever see ciphertext, not your actual data. You get up to 1GB free with no account, and if you sign in with a Firefox account that jumps to 2.5GB. You set an expiration on the link yourself, either by number of downloads or by time, and once that's hit the file is gone, not "archived," not "available on request," actually deleted. You can slap a password on the link too, on top of the encryption, if you're sending something you'd rather not have sitting unprotected even briefly.
I tested it on a 380MB video file last Wednesday, set it to expire after one download, sent the link to a friend, and watched it disappear from Mozilla's end the second he grabbed it. No sign-up wall on his end, no "create an account to download this," which is the thing that annoys me most about the competition. You shouldn't need an account to receive a file someone sent you.
None of this is revolutionary as a concept, obviously, people have been building temporary-file-drop services for a decade. What I like is that it's Mozilla doing it, not some ad-funded startup with a business model I have to be suspicious of. There's no tracking pixel nonsense, no "we sell anonymized usage data" clause buried in a privacy policy nobody reads. And it's just at send.firefox.com, works in any browser, not just Firefox, which surprised me a little.
A small complaint, since I promised myself years ago I'd stop writing posts that are just unqualified praise for things: the interface for setting expiration options is a little buried, tucked behind a settings icon most people are going to miss on the first try. I had to go looking for it the first time. Not a dealbreaker, just the kind of small UX thing that makes me wonder if anyone user-tested the first-run flow with someone who wasn't already a Mozilla employee.
These days when someone actually needs a file from me long-term, not just a one-off transfer, I don't bother with any of this and just drop it on the VPS I run through Tricknowtech and hand them a direct link. It's been running fine for months without me touching it, which is honestly the highest compliment I can give a hosting setup at this point in my life. But for the quick, one-time, "here's a file, forget it exists in three days" case, Send has replaced WeTransfer for me completely, and I don't think I'm going back.
If you haven't tried it yet, go dump something disposable into it just to see the flow. It's free, it doesn't ask for your email address, and if Mozilla keeps this running the way they've kept Send's older Test Pilot sibling running, it'll probably still be here next year, which is more than I can say for half the file-sharing tools I bookmarked in 2015.