Image Tools
Image Compressor
Re-encode one static raster as JPEG or WebP without guaranteeing a smaller file.
Enter the values and review the result.
Compression settings
Processing stays in this browser and makes no file-upload or conversion request.
One static JPEG, PNG, or WebP; 1 byte–8 MiB; at most 8192 px per side and 16000000 pixels.
Choose a validated image and compression settings.
Bounded browser re-encoding
The tool checks the declared MIME, JPEG/PNG/WebP signature, static-image structure, stored geometry, browser decode, and decoded geometry before drawing. Quality is divided by 100 only after strict validation. The requested output MIME must match the encoder Blob exactly.
JPEG output receives an opaque white canvas before drawing. WebP may retain alpha. Animation is rejected rather than silently flattened.
Worked example and limitations
A 1200 × 800 PNG can be re-encoded as WebP at quality 80 while remaining 1200 × 800. The resulting byte count cannot be predicted and may be larger or smaller.
Canvas output may omit metadata, normalize decoded orientation, or change color and profile behavior. Review the downloaded output. Processing is local, but this is not guaranteed privacy, deletion, malware scanning, archival fidelity, or regulatory compliance.
Quick answers
What this calculator answers
- Purpose: Re-encodes one validated static raster as JPEG or WebP without resizing it.
- Limits: Accepts JPEG, PNG, or WebP up to 8 MiB, 8192 pixels per side, and 16000000 decoded pixels.
- Boundary: Output can be larger than the source; this tool does not guarantee reduction, metadata preservation, or lossless quality.
Transparency note
Accuracy and limitations
Calzivo tools are built for practical estimates, conversions, and checks. Some tools use standard formulas or simplified assumptions, and results can be affected by input accuracy, rounding, units, local rules, or changing official requirements.
File and image results can vary by file structure, browser support, size, fonts, compression, and format limits. Review downloaded files before using or sharing them, and avoid sensitive files unless you understand how the tool handles them.
Reference check
Sources and references
These references provide background context for the topic. They do not replace official advice or documents for personal decisions.
- File API
World Wide Web Consortium
- Canvas toBlob
WHATWG
- ImageBitmap and image decoding
WHATWG
How to Use This Tool
Use these steps to enter the right inputs and interpret the result correctly.
Choose one static JPEG, PNG, or WebP file.
Select JPEG or WebP output and a whole-number quality from 1 to 100.
Choose Compress Image, review the preview and signed size change, then download or Reset.
Related Tools
Other helpful tools in the Image Tools category.
Image Resizer
Change bounded static raster pixel dimensions with an optional aspect-ratio lock.
Image to Base64
Encode validated original JPEG, PNG, or WebP bytes as a Data URL or raw Base64.
Base64 to Image
Strictly decode canonical Base64 into a validated static JPEG, PNG, or WebP image.
JPG to PDF
Create one PDF from ordered JPEG images with automatic page sizing.
PDF to JPG
Convert every PDF page to a JPG image and download the ordered pages as a ZIP.
Related Guides
Background reading and explanations related to Image Compressor.
Frequently Asked Questions
Common questions about Image Compressor and how to read the result.
Will the output always be smaller?
No. Re-encoding can increase, decrease, or leave file size unchanged depending on the source, format, quality, and browser encoder.
What happens to transparency?
JPEG output fills transparent pixels with white. WebP may preserve transparency when the browser encoder supports it.
Are animated images supported?
No. GIF, animated PNG, animated WebP, SVG, and other unsupported formats are rejected before processing.
Does compression remove metadata?
Canvas re-encoding may omit embedded metadata, normalize orientation, or change color-profile behavior, but it is not a guaranteed metadata-removal service.