Compress PDF to 100 KB
Choose a PDF and compress it to under 100,000 bytes. A single scanned page fits with room to spare, two or three fit at lower resolution, and five mixed pages did not fit in our tests. When a file cannot fit, the tool says so and names the smallest size it can make, instead of handing back a file that is over your limit. It runs in your browser, so nothing is uploaded.
Make a PDF under 100 KB
Nothing is uploadedStays under 100,000 bytes, below the limit whether the portal counts 1 KB as 1,000 or 1,024 bytes. Up to 20 pages.
Leave it empty to keep every page. To send only some, write them like 1-2 or 1, 3. The size limit then applies to the pages you keep.
What 100 KB means for a PDF.
A budget shared by every page. The limit is for the whole file, so each extra page takes space from the others. One phone-scanned certificate came out at 97.2 KB and 96 DPI. Two scanned sides had to share the allowance and dropped to 67 DPI. Three pages reached 97.9 KB only at the tool's floor of 60 DPI, with JPG quality 59.
What the DPI number looks like on the page. At 100 DPI a line of 10-point type is about 14 pixels tall. At the 60 DPI floor it is about 8. Typed certificates usually stay readable near 100 DPI; small print at 60 DPI often does not. The result panel shows the DPI the tool used and warns when it went below 100, so read the smallest text in the file before you upload it.
A typed PDF is already small. A PDF exported from Word or a browser stores letters, not pixels. Our three-page typed test file was 42 KB and a twelve-page one 65 KB, both under 100 KB, so the tool hands them back unchanged. This page is for PDFs made from scans and photos.
Official notices that use 100 KB for a PDF
Among the notices we read, none sets 100 KB as the largest allowed PDF. The one exact match runs the other way: 100 KB is where DRDO's range starts. The row was read in DRDO's own file on 29 Sep 2026.
| Notice and file | Official rule and source |
|---|---|
| CEPTAM-11, How to ApplyEssential qualification certificates, Class X certificate and reservation certificates, scanned in true colour | PDF only, 100 kB to 1 MBDRDO (CEPTAM) (opens in a new tab) How to Apply, page 1, note under the list of documents (file dated 28 Jun 2025), checked 29 Sept 2026 |
DRDO asks for at least 100 kB, so a file this tool keeps under 100,000 bytes can never meet it. For a range like that, use a larger limit: the 200 KB page makes files close to its limit, which lands inside 100 kB to 1 MB, unless your file is already under 200 KB, in which case it is returned unchanged and you should check that it is above 100 kB. If your own form says 100 KB, the number comes from that portal's upload screen or notice, and that is the one to follow.
What fits in 100 KB
Six files at a 100 KB limit. One and two scanned pages fit, three fit only at the floor, and five mixed pages did not. Every file is computer-generated (invented content) except UPSC's own instructions PDF.
| File | Before | At 100 KB |
|---|---|---|
| A typed letter exported from a browser | 42 KB3 pages | Already under 100 KBReturned unchanged |
| One certificate, photographed by a phone scanner | 283 KB1 page | 97.2 KB96 DPI, JPG quality 68 |
| Front and back of a certificate, scanned | 605 KB2 pages | 98.2 KB67 DPI, JPG quality 71 |
| Three scanned pages | 912 KB3 pages | 97.9 KB60 DPI, JPG quality 59 |
| Five pages: text, scans and a photograph | 595 KB5 pages | Does not fitSmallest the tool could make: 105 KB |
| UPSC's own instructions PDF, a real documentupsconline.nic.in, read 2026-09-29 (opens in a new tab) | 847 KB4 pages | Does not fitSmallest the tool could make: 120 KB |
KB here is 1,000 bytes; a refusal quotes the tool's message, which counts 1,024. Chrome, 29 Sept 2026.
If your PDF will not go below 100 KB.
Keep only the pages the form asks for. Type the pages in Pages to keep, for example 1-2. The limit then applies to those pages only. One or two scanned pages fitted 100 KB in every test we ran, while the five-page mixed file was refused with 105 KB as the smallest it could make.
Use the size the tool reports, if the portal allows it. When the tool stops, it names the smallest file it can make: 105 KB for the five-page file, 120 KB for UPSC's four-page PDF. One click retries at the next 10 KB up. A file over the portal's limit is rejected however it was made, so use that button only when the limit is not fixed.
Export the source file instead of scanning it. A letter typed in Word and saved as PDF was 42 KB for three pages in our test. Scanning the printed copy gives a file several times larger. If you still have the original document, export it as PDF and skip the scan.
Check the number on the upload screen. A notice may say 100 KB in one place and a range in another. Read the upload screen itself, and use the 200 KB page when a notice lists a range such as 50 KB to 300 KB.
Why a portal sets a limit this small.
What the notices say. The notices we read state a size and a format and give no reason. IBPS's April 2026 upload guidelines do say what to do when a scan is over its limit: adjust the scanner's DPI and number of colours (opens in a new tab). Those are the two settings this tool changes when it rebuilds a PDF.
A guess about the reason. A portal that receives lakhs of files keeps each one small so that uploads finish on a slow phone connection and storage stays manageable. That is our inference, not a statement from any notice; which portal sets which limit is the portal's decision.
Other sizes and tools.
If 100 KB is not the number on your form.
Questions
How do I compress a PDF to 100 KB?
Choose the PDF, leave the limit at 100 KB and select Compress. Each page is redrawn at the highest resolution that keeps the JPG quality readable, and a new PDF under 100,000 bytes is written. If the pages cannot fit, the message names the smallest size it can reach.
Can I compress a PDF to 100 KB without losing quality?
Not entirely: every page is saved again as a JPG, so some detail goes. In our runs one page kept 96 to 105 DPI at JPG quality 68, which reads well for typed text. Three pages dropped to 60 DPI.
How many pages fit in 100 KB?
One to three scanned pages in our tests: one at about 100 DPI, two at 67, three at 60. Five mixed pages did not fit, and UPSC's four-page instructions PDF needed at least 120 KB. A typed PDF is different: the tool leaves it alone when it is already under the limit.
How do I reduce a PDF to 100 KB on my phone?
Open this page in the phone's browser, pick the PDF from Files or from the scanner app's export folder, and select Compress. The download goes to the browser's usual folder, often Downloads. A big scan can take a few seconds because each page is redrawn.
Why does the tool say my PDF will not fit?
Because even at 60 DPI and its lowest JPG quality, the pages add up to more than 100,000 bytes. That happens with more than three scanned pages, or with large paper such as A3. The message gives the smallest size it can make, and Pages to keep lets you send fewer pages.
My form says 100 KB to 1 MB. Is this the right page?
No. That range starts at 100 KB, and this tool keeps the file below it. DRDO's CEPTAM instructions use exactly that range for PDFs, with the source linked above. Use a larger limit, such as the 200 KB page, so the file lands inside the range.
Is 100 KB 100,000 or 102,400 bytes?
Portals differ. The tool keeps the file below 100,000 bytes, so it is under the limit on either count. Windows and many upload screens show such a file as about 95 to 98 KB.
Does my PDF go to a server?
No. The file is opened, redrawn and rewritten inside your browser tab, and its pages never leave your device.
What this page cannot decide.
The tool keeps the file under 100,000 bytes and every page at its original size. Whether the portal accepts the document, and whether the person checking it can read the small print, is decided after you upload. Open the result first.
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