Summary
An image noise reducer is a tool that smooths the random grain and colour speckle that high ISO, dim light and small phone sensors leave in a photo. To reduce noise free and privately with this one, choose or drop your photos, keep the defaults (Strength 50%, Preserve details 60%), compare before and after with the eye button, and download. The filtering runs in your browser and nothing is uploaded, which you can confirm in the Network tab of DevTools.
The method is a bilateral filter: each pixel is averaged with nearby pixels of similar brightness, while pixels across a strong edge count for almost nothing, so outlines stay sharp. It is not AI denoising, so it suits mild to moderate noise. If the result looks soft, finish with the image sharpener, then shrink the file with the image compressor.
Table of Use: Photo Problems and Starting Settings
These are starting points; judge each result with the actual-pixels comparison.
| Situation | Suggested settings | What you get |
|---|---|---|
| Indoor or evening JPG shot at high ISO | Strength 60–70%, Preserve details 40–50%, both noise types ticked | Smoother shadows; a JPG at 95% quality named photo_denoised.jpg |
| Phone photo with coloured shadow blotches | Untick Luminance noise, keep Colour noise ticked | Only the colour channels are smoothed; brightness is left as it was |
| Portrait, hair or fabric you want to keep detailed | Strength 20–30%, Preserve details 70–80% | Light smoothing with fine texture kept |
| Scanned print or film grain | Strength 40–60%, Output format PNG (lossless) | A PNG with no extra compression loss |
| A whole shoot of 20 photos | Set options first, then add every photo together | The same settings on each, then one denoised-images.zip |
Features
- Two kinds of noise, handled separately. The image is split into brightness and two colour channels (YCbCr, as in JPEG). Colour noise is smoothed on the two colour channels only, over a wider window; colours are averaged rather than pulled toward grey, so overall saturation is kept.
- Strength and Preserve details sliders, each 0–100%. Strength 0% leaves the image unchanged.
- Before and after comparison, fit to box or actual pixels with the panes scrolling together.
- Batch processing with no preset limit and a single ZIP download.
- Output control: the original format (JPG and WebP at 95% quality, or PNG) or lossless PNG. Fully transparent pixels are left untouched.
- Private by design. No upload and no account. EXIF and GPS tags are not copied into the new file, because the result is re-encoded from the image pixels.
Strength sets how far the filter looks around each pixel, in a horizontal then a vertical pass:
| Strength | Brightness reach (pixels each side) | Colour reach (pixels each side) |
|---|---|---|
| 0% | Not filtered | Not filtered |
| 25% | 2 | 3 |
| 50% | 3 | 4 |
| 75% | 3 | 5 |
| 100% | 4 | 6 |
Banding and hot pixels are not random grain: banding is a smooth pattern, and a hot pixel differs so much from its neighbours that the edge-preserving filter keeps it as detail, so neither is removed. An image too large for your browser shows an error on its own card; the rest carry on. To soften an image on purpose, use the image blur tool.
How to Use the Image Noise Reducer
- Set Strength, Preserve details, the Luminance noise and Colour noise checkboxes and the Output format. Processing starts as soon as an image is added, so do this first.
- Click Choose images or drag photos onto the upload area. Files that are not images are skipped with a notice.
- Press the eye button to compare Original and Denoised. Switch Comparison: fit to box to Comparison: actual pixels to inspect at 100%.
- Changed a setting? Click Apply new settings to redo the finished images.
- Press Download on one image or Download all (ZIP) for several, then Clear all.
Who Can Use It
Photographers use it on high-ISO event and night shots, phone users on dim indoor photos. Sellers can pair it with the brightness adjuster or contrast adjuster.
Bloggers can reframe the cleaned photo with the image cropper, size it with the image resizer, make social thumbnails with the thumbnail generator, or switch formats with the PNG to JPG converter.
FAQs
How do I reduce noise in a photo online for free?
Click Choose images, or drag photos onto the upload area, and wait for processing to finish. Use the eye button to compare Original and Denoised, then press Download. The defaults are Strength 50% and Preserve details 60%, with luminance and colour noise both ticked. There is no account or watermark.
Is it safe to denoise my photos here, or are they uploaded?
Your photos are not uploaded. Decoding, filtering and encoding all happen in your browser, so you can open the Network tab in DevTools while you work and see no image data leave the page. The tool never sends your photos anywhere; the only file it loads on demand is its ZIP library, from this site, when you press Download all (ZIP).
What is the difference between luminance noise and colour noise?
Luminance noise is random grain in brightness, like film grain. Colour noise, also called chroma noise, is random red, green and blue blotches, most visible in shadows and skies. This tool filters them separately: the Luminance noise option smooths brightness, and the Colour noise option smooths only the colour channels.
Does this noise reducer use AI?
No. It uses a bilateral filter, a fixed edge-preserving algorithm that averages each pixel with neighbours of similar brightness and gives almost no weight to pixels across a strong edge. Extreme noise from very high ISO may need a machine-learning denoiser, which would require large model downloads.
Why does my photo look blurry or plastic after reducing noise?
Any denoiser trades some fine texture for smoothness, and very fine detail about as strong as the noise gets softened too. Lower Strength, raise Preserve details, and judge the result with Comparison: actual pixels rather than the fitted preview. A light pass with the image sharpener afterwards can restore some apparent crispness.
How do I remove noise from many photos at once?
Set Strength, Preserve details and the noise types first, then select or drop all the photos together. They are processed one after another with the same settings. When all are ready, press Download all (ZIP) to get one denoised-images.zip file. There is no preset batch limit; your device memory and speed set the practical one.
Should I reduce noise before or after sharpening a photo?
Reduce noise first. Sharpening increases local contrast, so it also exaggerates grain, and denoising a sharpened image removes some of the sharpness you just added. A common order is noise reduction, then exposure and contrast, then resizing to the final dimensions, then gentle sharpening.