Compress & Convert
Compress and convert JPEG, PNG, WebP, and BMP images. All processing happens in your browser.
Drag & drop images here, or click to select
ποΈ Preview
1/1
Compression Settings
80%
100%
β FAQ β Image Compression & Conversion
This is not a bug β it's due to how image formats work. There are two main causes:
1. The original was a low-quality JPEG
For example, if the original was saved at 40% quality and you re-encode at 80% quality, the amount of data increases and the file becomes larger. Set the quality slider lower than the original image's quality.
2. The original was a PNG
PNG uses lossless compression, so the quality slider has no effect. The browser's Canvas API PNG output is not as optimized as dedicated image editors, so the result may be larger than the original.
Solution: Switch the output format to
1. The original was a low-quality JPEG
For example, if the original was saved at 40% quality and you re-encode at 80% quality, the amount of data increases and the file becomes larger. Set the quality slider lower than the original image's quality.
2. The original was a PNG
PNG uses lossless compression, so the quality slider has no effect. The browser's Canvas API PNG output is not as optimized as dedicated image editors, so the result may be larger than the original.
Solution: Switch the output format to
WebP β it tends to produce significantly smaller files regardless of whether the original is JPEG or PNG.For JPEG/WebP:
- Quality 80-90%: Virtually no visible difference, 30-60% size reduction
- Quality 60-79%: Slight degradation on close inspection, 50-75% size reduction
- Quality 40-59%: Block noise visible when zoomed in, 70-85% size reduction
- Quality 10-39%: Obvious degradation, suitable for thumbnails
We recommend using the "Compare" mode in the preview to check the actual appearance while adjusting.
For PNG: Since PNG uses lossless compression, the quality slider has no effect. To reduce size, switch the output format to WebP.
- Quality 80-90%: Virtually no visible difference, 30-60% size reduction
- Quality 60-79%: Slight degradation on close inspection, 50-75% size reduction
- Quality 40-59%: Block noise visible when zoomed in, 70-85% size reduction
- Quality 10-39%: Obvious degradation, suitable for thumbnails
We recommend using the "Compare" mode in the preview to check the actual appearance while adjusting.
For PNG: Since PNG uses lossless compression, the quality slider has no effect. To reduce size, switch the output format to WebP.
WebP is an image format developed by Google.
- JPEG: Best for photos, lossy compression, no transparency support
- PNG: Best for illustrations/screenshots, lossless compression, supports transparency
- WebP: Combines the best of both, 25-35% smaller than JPEG at the same quality
Nearly all modern browsers support WebP. However, some older software (e.g., Word 2016 and earlier) may not open WebP files. For web use, WebP is highly recommended.
- JPEG: Best for photos, lossy compression, no transparency support
- PNG: Best for illustrations/screenshots, lossless compression, supports transparency
- WebP: Combines the best of both, 25-35% smaller than JPEG at the same quality
Nearly all modern browsers support WebP. However, some older software (e.g., Word 2016 and earlier) may not open WebP files. For web use, WebP is highly recommended.
Since the pixel count is reduced, the image will appear less sharp if enlarged again. However, for practical use cases like websites and email attachments, resizing to an appropriate size causes virtually no noticeable quality loss.
Example: Resizing a 4000x3000px smartphone photo to 50% (2000x1500px) for web use β the difference is imperceptible on screen.
Combining resize with quality adjustment is the most efficient way to reduce file size.
Example: Resizing a 4000x3000px smartphone photo to 50% (2000x1500px) for web use β the difference is imperceptible on screen.
Combining resize with quality adjustment is the most efficient way to reduce file size.
Yes, you can process any number of images simultaneously. Drag multiple files onto the drop zone, or select multiple files in the file dialog.
- For 1 image: The compressed image downloads directly
- For 2+ images: All are bundled into a ZIP file for download
The same settings (quality, format, resize) are applied to all images. Use the ββΆ buttons in the preview to check the results for each image.
- For 1 image: The compressed image downloads directly
- For 2+ images: All are bundled into a ZIP file for download
The same settings (quality, format, resize) are applied to all images. Use the ββΆ buttons in the preview to check the results for each image.
No, images are never sent to any server. All processing is completed entirely within your browser.
Technically, it uses the browser's
You can safely use this tool with confidential images and personal photos.
Technically, it uses the browser's
Canvas API and OffscreenCanvas, and no network communication occurs. When you close the page, all data used for processing is cleared from memory.You can safely use this tool with confidential images and personal photos.
Input: JPEG, PNG, WebP, BMP, GIF, SVG (rasterized), AVIF (when supported by browser)
Output: JPEG, PNG, WebP
When BMP or GIF is used as input with "Keep Original Format" selected, the output is automatically converted to PNG. HEIC (iPhone's default format) support varies by browser. The latest version of Chrome supports it, but if unsupported, please convert to JPEG first before using this tool.
Output: JPEG, PNG, WebP
When BMP or GIF is used as input with "Keep Original Format" selected, the output is automatically converted to PNG. HEIC (iPhone's default format) support varies by browser. The latest version of Chrome supports it, but if unsupported, please convert to JPEG first before using this tool.
They can be processed, but it depends on your browser's memory. As a guideline:
- Under 10MB: No issues
- 10-50MB: May take a few seconds to process
- Over 50MB: Browser may run out of memory
Processing many large images simultaneously may cause the tab to crash. In that case, process them in smaller batches.
- Under 10MB: No issues
- 10-50MB: May take a few seconds to process
- Over 50MB: Browser may run out of memory
Processing many large images simultaneously may cause the tab to crash. In that case, process them in smaller batches.
When you compress or convert with this tool, EXIF data is automatically removed. This is due to the Canvas API re-rendering process.
This is actually a benefit from a privacy perspective (as GPS location data is removed). However, if you need to preserve shooting date or camera information, please be aware that EXIF data will be lost after processing with this tool.
This is actually a benefit from a privacy perspective (as GPS location data is removed). However, if you need to preserve shooting date or camera information, please be aware that EXIF data will be lost after processing with this tool.
This tool does not modify the original image. Compressed results are downloaded as new files, so your originals remain untouched.
However, once an image is saved with lossy compression (JPEG or WebP), the original quality cannot be restored. Always keep your original files as backups.
However, once an image is saved with lossy compression (JPEG or WebP), the original quality cannot be restored. Always keep your original files as backups.
Crop
Crop images to a specified size or aspect ratio.
Drag & drop an image here, or click to select
Crop Settings
Γ
px
92%
β FAQ β Crop
If you set the output quality high (90% or above recommended), there is virtually no visible degradation. Selecting PNG format gives you lossless compression with zero quality loss.
Since the cropped area has fewer pixels than the original, the file size is usually smaller.
Since the cropped area has fewer pixels than the original, the file size is usually smaller.
If the specified size exceeds the original image dimensions, the maximum crop area within the original image is automatically set. The image will not be upscaled.
1200Γ600 β OGP images (social media share thumbnails)
1080Γ1080 β Instagram posts
300Γ300 β Icons and thumbnails
640Γ480 β Standard web image size
For custom dimensions, enter pixel values in the "Custom Size" fields.
1080Γ1080 β Instagram posts
300Γ300 β Icons and thumbnails
640Γ480 β Standard web image size
For custom dimensions, enter pixel values in the "Custom Size" fields.
Currently, cropping supports one image at a time. This is by design, as the crop area is interactively adjusted for each image.
If you need to resize multiple images to the same dimensions, use the resize feature in the "Compress & Convert" tab.
If you need to resize multiple images to the same dimensions, use the resize feature in the "Compress & Convert" tab.
No. The cropped result is downloaded as a new file. The original image is not modified in any way.
Watermark
Add text watermarks to your images.
Drag & drop images here, or click to select
ποΈ Preview
1/1
Watermark Settings
Custom
30%
-30Β°
β FAQ β Watermark
When using tile (repeat) mode to place watermarks across the entire image, complete removal becomes very difficult even with image editing software. A single placement (e.g., center only) can be bypassed by cropping, so tile mode is recommended for important images.
However, with advances in AI image restoration technology, no watermark is completely impossible to remove. Use it as a deterrent against unauthorized use.
However, with advances in AI image restoration technology, no watermark is completely impossible to remove. Use it as a deterrent against unauthorized use.
You can use CSS color format in the color input field.
Common settings:
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-
The last value (0-1) is the opacity. A range of 0.2-0.4 provides a good balance between visibility and aesthetics. Adjust while checking the preview.
Common settings:
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rgba(255,0,0,0.3) β Red, 30% opacity (recommended)-
rgba(0,0,0,0.2) β Black, 20% opacity-
rgba(255,255,255,0.4) β White, 40% opacity (for dark images)-
rgba(0,0,255,0.25) β Blue, 25% opacityThe last value (0-1) is the opacity. A range of 0.2-0.4 provides a good balance between visibility and aesthetics. Adjust while checking the preview.
Yes, multi-language text is supported. You can enter text in Japanese, Chinese, Korean, or any other language directly.
Internally, it uses fonts installed in your browser (such as Noto Sans JP), so it depends on your system's font environment. Standard Windows and Mac systems should display text without any issues.
Internally, it uses fonts installed in your browser (such as Noto Sans JP), so it depends on your system's font environment. Standard Windows and Mac systems should display text without any issues.
Guidelines based on image pixel dimensions:
- Small images (under 800px): 24-36px
- Standard images (800-2000px): 36-60px
- Large images (over 2000px): 60-120px
In tile mode, larger text can overlap. Using a smaller size with higher density creates a more effective watermark.
- Small images (under 800px): 24-36px
- Standard images (800-2000px): 36-60px
- Large images (over 2000px): 60-120px
In tile mode, larger text can overlap. Using a smaller size with higher density creates a more effective watermark.
Since the output uses the same format as the original, areas outside the watermark retain the original quality. JPEG images are re-encoded at 92% quality.
For completely lossless output, use a PNG original β it will be output as PNG with no degradation.
For completely lossless output, use a PNG original β it will be output as PNG with no degradation.
The current version supports text watermarks only. Image watermark support (for logos, etc.) is being considered for a future update.
As an alternative, you can use the Β© symbol or your company name as a text watermark for basic branding.
As an alternative, you can use the Β© symbol or your company name as a text watermark for basic branding.
Generally, -30Β° to -45Β° is most commonly used.
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Combined with tile mode, any angle works effectively.
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-45Β°: Most popular. The text crosses the image diagonally, making it hard to crop out-
-30Β°: Slightly gentler angle, easier to read (default setting)-
0Β°: Horizontal placement. Text is readable but easier to remove by croppingCombined with tile mode, any angle works effectively.
Batch Rename
Rename multiple files with sequential numbers and download as ZIP.
Drag & drop files here, or click to select
Rename Settings
Example: file_001.jpg, file_002.jpg β¦
β FAQ β Batch Rename
Files are numbered in the order they were added via drag & drop or file selection. To change the order, drag items within the file list to rearrange them.
Note that the OS file dialog typically selects files in alphabetical order by filename.
Note that the OS file dialog typically selects files in alphabetical order by filename.
Original extensions are preserved. For example, with prefix "photo_":
- IMG_001.jpg β photo_001.jpg
- screenshot.png β photo_002.png
Extensions are not changed (no format conversion).
- IMG_001.jpg β photo_001.jpg
- screenshot.png β photo_002.png
Extensions are not changed (no format conversion).
Yes, all file types are supported. PDFs, Excel files, Word documents, videos, audio files β any file can be renamed and bundled into a ZIP.
No, original files are never modified. Renamed files are downloaded as a new ZIP file only.
There is no strict limit, but it depends on your browser's memory. A few hundred files should be fine, but processing many large files (e.g., videos) simultaneously may cause memory issues.