PDF File Size Compression Tool

Compress PDF file size with multiple compression modes and custom image quality DPI settings. Supports single-file or batch processing.

Bug report

Browser execution mode: Your data is processed in your browser and is not uploaded to the server.

Speed and Stability: Processing speed depends on your device and browser. For large batch work, the desktop version may be more stable.

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If the online tool fails to load or run, try the desktop tool.https://tools.yikeaigc.com/

Tool Usage

Return to old version

Add PDF files first, then set compression mode, image quality, and DPI, then process and download. Only the first 20 batch files are shown, but all files will be processed.

Select PDFs to compress

Files are read and processed in this page. Drag files to the area below, or load a sample PDF to test settings first.

Local processing

Drop PDF files here, or click to choose

You can select multiple PDFs at once. Only the first 20 are previewed, but all selected files will be compressed.

File count0

Original size0 B

Preview Count0

File preview Waiting for selection

Please select a PDF file, or use sample data to try the workflow.

Set compression parameters

Choose a processing mode first, then adjust image quality, DPI, and target file size for your use case. Saved settings can be restored automatically next time.

Set before processing

Processing Method Page rebuild gives stronger compression; structure cleanup keeps text and vector content, but saves less space.

Smart select Automatically choose between page rebuild and structure cleanup based on file content. Rebuild pages Render pages by DPI and regenerate the PDF. Best for images or scanned files. Structure cleanup Rewrite the PDF structure, remove metadata and comments, and keep text selectable.

Compression preset Choosing a preset adjusts the settings below; you can still fine-tune them.

Image quality and resolution Lower DPI makes files smaller, but also reduces text edges and image detail.

Image quality

62%

Output DPI

144

Page image format

Color scheme

Max pixels per page

Batch ZIP file name

Target size and cleanup options Target size is approached by lowering quality and DPI; not guaranteed for every file.

Enable target size

Target value

Unit

Keep smaller result onlyIf compression makes it larger, output the original file instead. Remove metadataRemove document properties such as author, title, and creation time. Remove commentsRemove comments during structure cleanup; page rebuild naturally ignores interactive comments. Include processing reportWrite a JSON report to the batch ZIP for saving settings and results.

Process & Download

Confirm files and settings, then start compression. Multiple PDFs will be packed as a ZIP. Compressed file names match originals by default; duplicates get a number automatically.

Output Result

Pending0

Estimation methodSmart select

Current Parameters62% / 144 DPI

Waiting to start.

Processing logs will appear here.

Compression results Waiting

Succeeded0

Output size0 B

Save space0%

Result preview Show first 20

Results will appear here after compression is complete.

Instructions

Software Usage Instructions

Add PDF files: Click the “Select PDF Files” button to choose one or more PDF files to compress, or drag and drop files into the upload area. For batch files, only the first 20 are displayed, but all files will be included during processing.
Load sample data: If you do not have a test file at the moment, click “Load Sample Data” to generate a sample PDF and first become familiar with the compression process and parameter effects.
Select a processing method:
- Smart selection: Automatically selects page rebuilding or structure cleanup based on the file content.
- Page rebuilding: Renders PDF pages according to DPI and regenerates the PDF, suitable for scanned files and materials with many images.
- Structure cleanup: Rewrites the PDF structure and cleans up some data, suitable for documents where selectable text needs to be preserved.
Set compression parameters:
- Compression preset: Choose Balanced Mode, High Compression, High Quality, or Structure Cleanup.
- Image quality: The lower the value, the smaller the file size usually is, but image clarity will decrease.
- Output DPI: 72DPI is suitable for screen viewing, 144DPI is suitable for everyday sharing, and 200DPI or above is suitable for clear reading or printing.
- Color mode: Keep color, or convert to grayscale to reduce file size.
Set target size: After checking “Enable Target Size,” you can enter a KB or MB value, and the tool will try to approach the target size by adjusting quality and DPI.
Select cleanup options: Choose options such as keeping only the smaller result, removing metadata, removing annotations, and including a processing report.
Save settings: Click “Save Settings” to save the current parameters, which will be automatically restored the next time you open the tool.
Start compression: After entering the “Process & Download” step, click “Start Compression” and wait for the progress to complete.
Download results: A single PDF will show a Download PDF button; multiple PDFs will be generated as a ZIP package. By default, compressed file names match the original file names, and numbers are automatically added when names are duplicated.

FAQ

A: Page rebuilding renders each page as an image and then regenerates the PDF. It is suitable for scanned files and files with many images, and usually provides more noticeable compression, but the text may no longer be selectable; structure cleanup rewrites the PDF structure and cleans up some data, making it suitable for documents where you want to preserve selectable text.

A: If it is for screen viewing or sending by email, you can choose a lower DPI and medium image quality; if it is for printing or clear reading, we recommend increasing the DPI and image quality. The higher the quality and DPI, the larger the output file usually is.

A: The compression result depends on the PDF content. Scanned files and image-based materials usually have more room for compression; PDFs with mostly plain text, many vector graphics, or that have already been compressed may show only a small change in size.

A: Not necessarily. The target size is approached by reducing quality and DPI, but whether it can be reached depends on the original PDF content, number of pages, image ratio, and existing compression level.

A: The original file names are kept by default. If multiple files have the same name, the tool will add a number after the file name to prevent them from overwriting each other when downloaded as a package.

A: Removing metadata mainly clears document properties such as author, title, and creation time; removing comments deletes annotations, form-related marks, and other additional content. The main page content is usually preserved.

A: Large files or PDFs with many pages consume more memory and processing time. You can lower the DPI, choose a high-compression preset, process files in batches, or close other resource-intensive programs.