About Mello

Mello is a directory of free utility tools that run entirely in your browser — 122 of them across formatting, calculation, design, image and PDF work, security, and a handful of long-form image guides. There is no account to create, no software to install, and nothing about your inputs is uploaded, stored, or shared.

Why this site exists

Most free online tools work by uploading your input to a server, processing it there, and sending the result back. For harmless inputs that is fine. For the inputs people most often want formatted, decoded, compressed, or converted, it is precisely the wrong arrangement: an API response from production, a JWT, a JPEG with embedded GPS coordinates, a scanned contract, a config file with secrets. Pasting any of those into a server-side tool means handing it to an operator you have no agreement with, who you cannot audit, and who frequently logs the traffic. Mello exists to give people a place to run those operations without making that trade.

How it works

Every tool here is a client-side JavaScript module. The site is statically generated, so each tool's page is pre-rendered HTML that loads only the script needed for that specific tool. Heavier libraries — pdf-lib, libheif, image-compression — are dynamic-imported on the routes that need them, so the shared bundle stays small. There is no server endpoint that handles tool inputs, by design. The browser's native APIs (Canvas, Web Crypto, the JSON and XML parsers) do the work.

Who runs it

Mello is operated by an independent publisher. The architecture — static generation, client-side execution, no backend — was chosen specifically so the site can stay free, fast, and private without needing a server team or a subscription model behind it.

How it is funded

Display advertising served via Google AdSense. Ad placements sit alongside the tools rather than interrupting them, and they cannot be personalized using anything you type into a tool — tool inputs never leave the browser, so there is nothing in them to personalize against. There are no premium tiers, no sign-up walls, and no data sold to third parties.

Contact

Have a tool idea, a bug to report, or a partnership inquiry? See the contact page.