Nothing is uploaded. When you drop or pick a PDF, the tool reads it locally with the browser’s File API, renders its pages in memory with the pdf.js engine (whose worker is bundled locally, not fetched from a CDN) and rebuilds the compressed file with the pdf-lib library on your own machine. There is no server, upload, database, API or tracking in the processing path, so CVs, certificates, ID scans, visa paperwork and other private documents you are shrinking for a form stay on your device; the tool works offline once cached, and closing the tab discards everything. The only optional network use anywhere on the site is consent-gated advertising, which never sees your files.

Reaching a target uses lossy compression — images are down-sampled to a lower DPI and re-encoded as JPEG, which is how a large file becomes small. But 1 MB leaves far more room than a 200 KB, 300 KB or 500 KB cap, so the downward sweep usually stops very early or is not needed at all: a text-only PDF is often already under 1 MB and passes almost untouched, scans stay noticeably crisp, and most documents meet 1 MB without whole pages being rebuilt as images, which keeps their text selectable and searchable. Three variants are generated in one pass (Best Quality, Balanced and Smallest) and the tool defaults to the best one that still fits. One honest note: when a very heavy, photo-laden document does need its pages rasterised to reach 1 MB, the text on those pages becomes part of the picture and is no longer selectable; if you need the text to stay live on such a file, a 2 MB target or a lossless PDF tool is gentler still. For almost every document headed to a 1 MB upload box, the result stays perfectly legible.

It depends on what is inside the PDF, but 1 MB is one of the easiest common targets to hit. The real savings come from re-encoding images, so a text-only or lightly formatted document usually already weighs less than 1 MB and needs little or no compression, and a typical certificate, mark sheet or multi-page scan reaches the cap with legibility to spare. A long scan full of photographs still has a floor: past a certain point the pages would turn to mush, so the tool stops at the smallest readable size it can reach and reports that figure with a note rather than producing an unusable file. If you are stuck above 1 MB, enabling grayscale, removing pages you do not need, or splitting the document first will usually get you under the cap. The three variants let you take the Smallest one when you need every byte, or Best Quality — the default — when 1 MB is comfortably met.

A 1 MB ceiling turns up constantly: many job portals require a CV or resume in PDF under 1 MB, visa and immigration forms and university admission systems cap individual documents at around 1 MB, court e-filing and older web forms reject anything larger, and a sub-megabyte attachment sends and delivers far more reliably than a multi-megabyte one that bounces off an inbox or gateway limit. A flatbed scanner on default settings produces roughly 2–4 MB per full-colour A4 page, so an untouched scan of a transcript, offer letter or ID can still exceed 1 MB — compression is the fastest fix that keeps the whole document. Because 1 MB is the roomiest of the common caps, the tool can compress very gently, so scanned certificates and photos keep their detail and text usually stays selectable while still clearing the field; it is also a safe margin under a 2 MB limit. This tool is built for exactly that: the target is fixed at 1 MB so you can drop the PDF and download a version that clears the limit, without hunting through compression settings. If the portal wants a smaller file, sibling tools target 500 KB, 300 KB and below, and larger presets (2 MB, 3 MB and up) exist for looser limits.