Community watch against scams
About us
Shield404 is an independent Spanish project, born from something very simple: being fed up with watching SMS, WhatsApp and phone scams hit thousands of people every day — especially older people — with no free tool, in plain language, to check the moment doubt strikes.
We're not a big company. We're a small project built with professional tools, maintained with great care, obsessed with one thing: when someone receives "that weird message", they have somewhere to check it in 5 seconds, for free, with no sign-up.
Why it's free (and will stay that way)
Because basic security shouldn't cost money, and because the person who needs it most — the one staring at a text message with their heart in their throat — isn't going to pull out a card to check it. Shield404 runs on services with free tiers and public cybersecurity sources, and its running cost is minimal by design.
There are no ads and there never will be. We don't sell data — in fact, we don't store it. You can read exactly what we process and what we don't in our privacy policy, written to be understood at a glance, and check our technical measures on the security page (ES), with instructions to verify them yourself. The legal identification of this project's owner is available in our terms of service (ES).
How the shield works
When you analyse a message, Shield404 checks it against several layers at once: its own rules engine (domains mimicking brands, scam language, shortened links, brand-new domains…), international public phishing and malware lists, and the community's own memory: what other users have already reported. Every report you make protects the next person.
Our commitment
- Honesty above all: when we don't know something, we say so ("Not verified") instead of giving a false sense of security.
- Plain language: no jargon. If your grandmother wouldn't understand it, we rewrite it.
- Privacy by design: no sign-up, no stored IPs, no tracking.
- Open door: if you're an association, senior centre, local council or media outlet and want to collaborate or spread the word about the tool, write to us: hola@shield404.com.