300 KB is roughly where greyscale at high quality and colour at low quality cost the same. The tool works down to the target in three stages and stops at the first that fits.
That equivalence is worth knowing, because it means the choice at this size is a real one: sharper pages without colour, or colour pages that are visibly softer.
A one-page colour ID scan starts around 250 KB, so it arrives under this cap without being touched. That is the character of the 300 KB tier: most single pages simply fit, and the work only begins when a document runs to several pages or was scanned at a resolution nobody needed.
Where the 300 KB limit comes from
- Government job and recruitment portals300 KB per document
- Bank KYC and account opening300 KB per page
- Court and e-filing intake forms300 KB to 1 MB
- Insurance claim document uploads300 KB per attachment
- Tender and procurement submission portals300 to 500 KB
This is the most forgiving of the tight caps, which changes the advice. Rather than fighting for every kilobyte, the aim is to arrive under the limit with the page still worth reading, and that usually means deciding what the document is for before deciding how to scan it.
How the tool hits 300 KB
Add the PDF
Files arriving at 300 KB are usually scans of two to four pages. The whole document is read into memory before any decision about quality is made.
Tidying, then a ladder that rarely runs out
Structure first, at no cost. The images then come down the rungs, and 300 KB is roughly where greyscale at high quality and colour at low quality cost about the same, so the ladder usually stops before the bottom.
Stage three, the exception at this size
Most documents reach 300 KB without a rebuild. The ones that do not are usually photographs of pages rather than scans of them, and for those the pages are rebuilt with the text layer kept behind.
Download, and read the result line
It names the rung. At this target the rung is worth reading, because it tells you whether you bought the size with resolution or with colour.
Structure, then the images in place, then the pages as pictures. It stops at the first stage that fits.
Untouched at the first two stages. If the pages do get rebuilt, an invisible text layer keeps them searchable.
The IDs, forms and statements people compress for portals never leave the device.
What fits in 300 KB, and what does not
Three or four greyscale pages, or about half that in colour. The cost of a page is set by how much detail it carries rather than by how much is written on it, which is why a photograph of a blank wall costs more than a page of dense text.
When it cannot reach 300 KB
At 300 KB the usual cause of a miss is colour that the document does not need. Three moves:
- Trade colour for resolution. A greyscale scan at high quality is sharper at 300 KB than a colour scan at low quality, and for a printed document it loses nothing that matters.
- Take out the pages carrying photographs. One photographic page sets the rung for the whole file. Split PDF, handle that page separately, and the rest stays crisp.
- Rescan rather than recompress. A fresh greyscale capture at 200 dpi will beat anything achievable by pushing an existing colour scan further down the ladder.
Greyscale at high quality, or colour at low
At this size the real choice is between a greyscale page with plenty of resolution and a colour page with less. Both land under 300 KB. They are not equally useful, and which one wins depends entirely on what the reader needs to see.
- Colour matters where the colour is evidence: a stamp, a seal, a signature in blue ink that has to be distinguishable from a photocopy, a coloured security feature on an ID. Keep the colour and accept the softer image.
- Resolution matters where the page is dense: small print, a table of figures, a handwritten form, anything with a barcode or a reference number somebody has to read. Go greyscale and spend the budget on sharpness.
One practical test settles it. Open the compressed file at 100 percent and read the smallest thing on the page. If a reference number, a date or a signature is ambiguous, the trade went the wrong way. Run the original again with the other choice rather than compressing the output a second time, which only compounds the damage.
Where people use the 300 KB target
- Government job application documents1 to 3 pages, fits
- KYC document sets1 page each, fits in colour
- Court filing exhibits2 to 4 pages, fits in greyscale
- Insurance claim forms and photographs1 to 2 pages, borderline in colour
Why this runs in your browser
The documents that meet a 300 KB limit are usually scans of official paperwork. A compression website would need a full copy of that paperwork to do its job, which is a poor trade for a smaller file.
The tool is right above
Everything on this page runs in your browser. Scroll up, drop the file, and keep it on your machine.
Common questions
What people ask when the form stops at 300 KB.
01What fits in 300 KB?
A single colour ID scan arrives around 250 KB and usually needs no work at all. Text documents of several pages fit easily. Multi-page colour scans are where it starts costing quality.
02Colour or greyscale at this size?
Colour when the colour is evidence, such as a stamp, seal or ink signature. Greyscale when the page is dense with small print or figures, because the saved budget buys sharpness.
03My file is already under 300 KB. Do I need this?
No. The tool checks first and hands a file that already fits straight back untouched. Send it as it is.
04Why do so many portals use 300 KB?
It is roughly the smallest cap at which one colour page stays legible, so it lets a portal accept colour documents without the storage cost of full-resolution scans.
05Will a scanned signature stay clear?
On a single page at 300 KB, yes. Across four pages sharing the same budget it may not, in which case split the document and upload the pages separately if the portal allows it.
06Will the text still be selectable?
Usually, yes. Most documents reach 300 KB in the first two stages with their text untouched.
07Are my files uploaded anywhere?
No. Rendering and compression run in your browser. The file never leaves the device.
08Is it free?
Free. Every tool, unlimited use, no signup.