Smtp Protocol Ref
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100 calls/day, no card, no spam. Built by one person, in public.
About SMTP
SMTP solves a specific problem that comes up daily for anyone dealing with developer and design work: doing it once, fast, without an account. Everything happens client-side, which means your files and data never leave your machine. The interface is intentionally minimal so you can focus on the task instead of learning the tool. Like everything else in the developer collection, it is free, ad-light, and works on mobile as well as desktop.
When you'd reach for SMTP
You're on a public or shared machine and don't want to leave traces of what you're working on.
Travelers, contractors, anyone working from a friend's computer.
Nothing is uploaded, nothing persists if you're not signed in.
You're cleaning up a folder of files that accumulated over a project and need to standardize them.
Designers, writers, and developers wrapping up deliverables.
Drop each file in, copy the output, move on.
You need to handle a one-off task right before a meeting and don't have time to install anything.
Anyone working remotely on a borrowed or restricted machine.
Open the page, get the result, paste it into your doc — under a minute.
You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.
Marketers and ops people whose primary tool is metered.
Stay productive without burning credits.
Frequently asked about SMTP
- What browsers does SMTP support?
- Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
- Does SMTP work on mobile?
- Yes, SMTP is fully responsive and tested on iOS Safari and Android Chrome.
- Can I use SMTP commercially?
- Yes. The output of SMTP belongs entirely to you, with no licensing restrictions.
- Do I need to create an account to use SMTP?
- No. SMTP works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
- Is SMTP really free?
- Yes — SMTP is free for unlimited personal use, with no account required and no watermark on the output.
