Convert a PDF to A4
Convert any PDF to A4 pages — Letter, Legal or odd sizes rescaled to fit exactly, portrait or landscape. Free, private, nothing ever uploaded.
- Runs in your browser
- Files are never uploaded
- Free, no account
Your PDF never leaves this tab — here is how to check
This page has no upload step and no server behind it. Two ways to confirm that yourself, neither of which requires trusting us:
- Turn off Wi-Fi or put the device in aeroplane mode after this page has loaded, then run the tool. It still works.
- Open your browser’s developer tools, switch to the Network tab, clear it, and process a file. No request appears.
The reason this matters: in 2025 the PDF service pdf.net was found exposing roughly 3.5 million user-uploaded documents, and formatter sites JSONFormatter.org and CodeBeautify leaked over 80,000 saved snippets containing live cloud credentials. Those are architectural failures — a file that is never sent cannot be exposed that way.
Why a form insists on A4
Upload portals for universities, visa applications, tax filings and tenders are usually wired to a print or archival pipeline configured for exactly one sheet size. A Letter-size page fed into an A4 pipeline either gets clipped at the bottom, gets scaled without warning, or trips an automated size check and lands in a manual review queue. Converting first is cheap; a rejected submission is not.
A4 is 210 × 297 mm — 595.28 × 841.89 points at 72 points to the inch. This tool writes those precise numbers into the page rectangle, so a validator that measures the MediaBox reports a true A4 sheet rather than something 3 mm out.
What happens to each page size
| Source size | Scale onto A4 | Visible effect |
|---|---|---|
| US Letter (216 × 279 mm) | ~97% | Thin white bands left and right; slightly smaller text |
| US Legal (216 × 356 mm) | ~83% | Noticeably smaller text; wide bands at the sides |
| A5 (148 × 210 mm) | ~142% | Enlarged to fill the sheet; images may look softer |
| A3 (297 × 420 mm) | ~71% | Fold-out tables become small but stay vector-sharp |
| A4 already | 100% | No change beyond a rebuilt page object |
Scaling is always uniform: the smaller of the two ratios is used and the page is centred, so the aspect ratio is preserved and nothing is ever stretched or cropped away.
Portrait, landscape, or match the page
The default, match each page, puts portrait sources on portrait A4 and landscape sources on landscape A4. That keeps a wide table readable instead of shrinking it to fit a portrait sheet.
Choose always portrait when the recipient requires a uniform document — every sheet the same way up. Wide pages will then be scaled down substantially, so check the scale column in the results table before you submit.
A4 and text sharpness
Scaling a PDF is not like scaling a JPEG. Text and vector graphics are described mathematically, so a page rendered at 97% is drawn afresh at that size and is exactly as crisp as the original at any zoom or print resolution.
Embedded photographs are the exception. A photo placed at 300 DPI on Letter becomes about 310 DPI on A4 — very slightly denser, which is an improvement. Scaling a small page up to A4 works the other way: an A5 scan at 300 DPI ends up around 210 DPI, which is still comfortably above the 150 DPI most print workflows treat as the floor.
Before you send it
- Open the result and confirm nothing important sits in the new white bands.
- If there is a file-size cap as well, run it through Compress PDF afterwards.
- Links and form fields are not carried over — re-check any interactive form before submitting.
- Print at actual size if you are printing rather than uploading.
Questions
What exactly is A4 in points?
A4 is 210 × 297 mm, which is 595.28 × 841.89 PostScript points at 72 points per inch. This tool writes those exact dimensions, so a checker that measures the page box will report a true A4 sheet rather than a rounded approximation.
My printer still says “scale to fit” — why?
Printers reserve a non-printable border of a few millimetres, so a full-bleed A4 page is always slightly larger than the printable area. That prompt is about the hardware margin, not about the page size, and you can safely accept it or print at 100% and lose a hair off each edge.
Does it rotate landscape pages to fit portrait A4?
It does not rotate them. With orientation set to “match each page”, a landscape source page is placed on a landscape A4 sheet so nothing shrinks unnecessarily. Force “always portrait” if every sheet must be the same way up, and wide pages will be scaled down to fit.
Why do universities and government portals insist on A4?
Because their print pipelines and archival scanners are configured for a single sheet size, and a Letter-size upload either gets clipped or triggers a manual review. Converting before you upload is usually the difference between an accepted and a rejected submission.