Security Architecture

Your Excel file never leaves your browser.

XLtoPDF is built on a zero-upload architecture. The entire conversion pipeline — file parsing, typesetting, and PDF generation — runs as JavaScript inside your browser tab. The instant the PDF downloads, your file is gone.

01

No network transmission

Your spreadsheet is read directly from disk into browser memory. There is no upload endpoint, no API call, no telemetry payload containing your data.

02

Volatile-only processing

Parsed rows live in volatile RAM for the duration of the conversion. When the PDF is delivered or you close the tab, that memory is released to the OS — instantly and irrecoverably.

03

Fully anonymous

No accounts, no email, no cookies, no fingerprinting. We have no way to associate a conversion with a person — because no conversion ever touches our infrastructure.

04

Verifiable in DevTools

Open your browser's Network tab during conversion. You will see zero outbound requests carrying your data. The PDF download is generated as a local Blob.

05

Open, audited dependencies

Conversion is powered by SheetJS and jsPDF — open-source libraries reviewed by the global JavaScript community.