File Hash & Malware Lookup

Compute a file's cryptographic hash in your browser, then check it against VirusTotal's threat database.

About this file hash & malware lookup

Antivirus engines identify known malware by hash. This tool computes a file's SHA-256 and SHA-1 entirely in your browser — your file is never uploaded — then hands the hash to VirusTotal's web lookup, which queries 70+ engines at once. Use it to verify a downloaded installer matches the publisher's published hash, or to check whether a suspicious attachment has already been flagged.

How to use File Hash & Malware Lookup

Open the page, enter the input you want to check, and the result appears immediately above — there is nothing to install, no account to create, and no popup to dismiss. Every Toolzer utility is designed to give you the answer on the first screen and let you copy or share it in one click. If the result looks unexpected, run the test a second time: transient network conditions, browser extensions, and corporate proxies can all affect single-shot measurements, and a fresh run usually confirms whether the issue is real or a one-off blip.

Every tool on Toolzer is built to work on desktop and mobile, including the latest versions of Chrome, Edge, Firefox, Safari, and Brave. Results are rendered directly in your browser whenever possible, so the page stays responsive even on slow connections. When a server lookup is required — for example to query public DNS, WHOIS, or geolocation databases — the request is proxied through Toolzer's edge so the third-party service never sees your IP address.

Privacy & how this tool works

Toolzer is a privacy-first toolbox: the page is served as a static, minified bundle with long-lived cache headers, so repeat visits are essentially free for both you and our servers. Inputs you type — text to format, passwords to generate, URLs to inspect — stay on your device unless an explicit server lookup is required. We do not sell data, we do not run third-party advertising trackers, and we do not require an account to use any tool on the site.

Bookmark this page and pair it with the other utilities listed below; together they cover most of the day-to-day SEO, networking, security, and developer tasks that would otherwise need three or four separate apps. If you spot a result you cannot explain, the FAQ underneath answers the most common questions about how the underlying measurement works and where its limits are.

Frequently asked questions

Is my file uploaded anywhere?+

No. Hashing runs in your browser via the Web Crypto API. Only the resulting hash string is sent — to VirusTotal — when you click the lookup button.

Why SHA-256 for malware lookup?+

SHA-256 is the industry standard for binary identification: collision-resistant, supported by every AV, and used by VirusTotal and major vendors as the primary key.

What if VirusTotal returns no results?+

It means no engine has seen that exact file before — common for new or rare files. Absence of a hit is not proof of safety; new malware variants appear constantly.

Are there file-size limits?+

Hashing happens in browser memory, so very large files (multi-GB) may slow your tab. For typical installers and documents performance is instant.

Do I need to create an account to use Toolzer?+

No. Every utility on Toolzer is free, anonymous, and works in any modern browser without registration. You will never see a paywall or a forced sign-up flow — the goal is to give you the answer on the first screen and let you move on.

Is Toolzer safe to use with sensitive inputs?+

Yes. Whenever the tool can produce an answer entirely in the browser — password generation, JSON formatting, regex testing, hashing, text counting — the data never leaves your device. When a server lookup is unavoidable (DNS, WHOIS, geolocation), the request is proxied through Toolzer's edge so the upstream service never sees your real IP address.

Does Toolzer work on mobile?+

Yes. The interface is fully responsive and works on iOS Safari, Android Chrome, Samsung Internet, and every other up-to-date mobile browser. You can pin the page to your home screen for one-tap access.

Can I link to or bookmark a result?+

Yes. Every Toolzer page has a clean, permanent URL you can bookmark, share, or paste into a ticket. Results are generated client-side on each visit, so the link always shows fresh data instead of a stale screenshot.