Guide · 7 min read

JPG to PDF size guide

Q: How do I reduce a JPG-to-PDF below a KB limit?

Use a converter that targets a file size instead of a fixed quality. Kodotools searches the JPEG quality until the PDF lands just under your number — pick your target size and convert.

Q: Does the size include multiple pages?

Yes — the KB target applies to the whole PDF. More pages means each image is compressed harder to stay under the same cap, so fewer, well-cropped pages give the best quality.

Q: Are my files uploaded anywhere?

No. The conversion runs entirely in your browser with JavaScript. Nothing is sent to a server, so your documents never leave your device.

Q: What if my exact size isn't in the list?

Open the JPG to PDF tool and type any KB value into the custom field. The size pages are shortcuts with the most common numbers pre-filled.

Most upload forms don't just want a PDF — they want it under a specific size: 100KB here, 500KB there, sometimes as little as 30KB. This guide explains how PDF file size actually works, which limit each kind of form uses, and links you straight to a tool that hits your exact KB target from your JPG photos — free, in your browser, nothing uploaded.

Updated July 2026. Written by Kodotools, a free browser-only tools project. Every tool below runs locally in your browser — no signup, no file uploads, no watermarks.

Pick your target size
PDF size	Typical use	Tool
30 KB	Ultra-tight portals, old govt forms	30KB →
80 KB	Strict single-page uploads	80KB →
Under 100 KB	The most common form cap	<100KB →
150 KB	Admission & KYC forms	150KB →
350 KB	Mid-range document uploads	350KB →
400 KB	"Under 400KB" portal limits	400KB →
450 KB	Visa & consular uploads	450KB →
500 KB	Higher-res multi-page scans	500KB →
A4 layout	Fit photos to a printable A4 page	A4 →
Any KB	Type your own exact number	JPG to PDF →

Don't see your exact number? Open JPG to PDF and type any KB value — the tool searches for the quality that lands just under it.

How PDF file size actually works

A PDF built from photos is basically a wrapper around compressed JPEG images. So the final KB comes down to three things:

Image resolution — a 4000×3000px phone photo carries far more data than a form thumbnail needs. Downscaling is the single biggest lever.
JPEG quality — dropping quality from 95% to ~70% often halves the size with no visible loss on a document.
Page count — each JPG you add is another compressed image, so a 3-page PDF is roughly 3× a 1-page one at the same quality.

Hitting an exact cap by hand means guessing quality, exporting, checking the KB, and repeating. The Kodotools converter does that search for you — it binary-searches the JPEG quality until the PDF lands just under your target.

Free tool

Just need it done?

Drop your JPGs, type your KB target, and download a PDF that lands under it — no accounts, no uploads.

Open JPG to PDF →

Which size does your form need?

If the form doesn't state a number, these patterns cover almost every case:

30–80 KB: older government and exam portals that were built for slow connections. Start at 30KB or 80KB.
Under 100 KB: the default limit on the widest range of forms — university, banking KYC, job portals. Use JPG to PDF below 100KB.
150–350 KB: admission systems and document uploads that allow a bit more detail. Try 150KB or 350KB.
400–500 KB: visa, consular, and multi-page scan uploads where readability matters. Use 400KB, 450KB, or 500KB.
Needs to print: if the PDF will be printed rather than just uploaded, lay your photos out on a proper page with JPG to A4 size PDF.

How to convert JPG to PDF at an exact size

Open the tool for your target — e.g. below 100KB — or use JPG to PDF and type your own KB number.
Drop in one or more JPGs. Drag to reorder if you're making a multi-page document.
Pick page size, orientation, and margin (or leave the defaults).
Confirm the KB target is set, then generate. The tool finds the quality that lands just under it.
Preview each page, then download. If a page looks soft, raise the target one step and re-run.

Tips for a clean, small PDF

Don't undershoot. If the cap is 500KB, landing at 60KB throws away readability you're allowed to keep. Aim just under the limit.
Crop before converting. Trimming empty margins removes data you don't need and makes the target easier to hit.
Shoot documents flat and evenly lit. Sharp, high-contrast source photos survive compression far better than shadowy ones.
iPhone photos are HEIC. Convert them with HEIC to JPG first, then build the PDF.
Need the image itself under a size? Compress the JPG first with the image compressor, then convert.

Frequently asked

How do I reduce a JPG-to-PDF below a KB limit?

Use a converter that targets a file size instead of a fixed quality. Kodotools searches the JPEG quality until the PDF lands just under your number — pick your target from the table above.

Does the size include multiple pages?

Yes — the KB target applies to the whole PDF. More pages means the tool compresses each image harder to stay under the same cap, so fewer, well-cropped pages give the best quality.