# Blur / replace photo background > Browser-only file conversion. Selected files are processed on this device and are not uploaded to a conversion server. Source: https://localconverter.tech/photo-background Keep the estimated subject while blurring the original background, replacing it with a solid colour or using another image. Adjust the segmentation cutoff and the relevant background settings to create a new PNG. This works best for clear subjects, with a final edge check against the chosen replacement. ## Useful tasks - Blur a portrait’s surroundings - Place a product on a solid colour - Replace a photo background with another image ## Steps 1. **Add the subject first**: Upload the subject photo first. For image replacement, add exactly one replacement background as the second file; blur and solid-colour modes use the subject alone. 2. **Select the background treatment**: Choose blur, solid colour or second image. Set blur radius or background colour where relevant, and leave cutoff at zero to retain a soft subject mask. 3. **Create the composite PNG**: Run Create output. The local model estimates the subject, then places it over the selected background treatment while fitting an uploaded background to the photo dimensions. 4. **Review the composite edges**: Download the PNG and inspect hair, transparent objects and contact edges. Check whether the replacement’s lighting and colours suit the subject before using the final image. ## Settings - **Background**: Choose background according to the result you need. Available choices: Blur original; Solid colour; Second image as background. The initial selection is Blur original. - **Blur radius**: Blur radius accepts values from 1 to 100, using whole numbers. The initial value is 20. Change it for a specific output requirement, then check the result before processing more files. - **Background colour**: Choose the background colour used by the operation. The initial colour is #ffffff. Check the output against its intended background, particularly when transparent areas, fine edges or text contrast matter. - **Mask cutoff (0 = soft)**: Mask cutoff (0 = soft) accepts values from 0 to 254, using whole numbers. The initial value is 0. Change it for a specific output requirement, then check the result before processing more files. ## A portrait on a neutral background A portrait has a distracting room behind it. Choose solid-colour mode and a light neutral background, keeping the soft mask initially. Create the PNG and check the hair and shoulder edges before placing the portrait in a team page layout. ## Check the result Upload a supported file, adjust the settings and create the output. Image replacement requires two files: subject first, background second. Local segmentation may leave edge artefacts. Open the saved output in the app or workflow where you plan to use it. Check one representative result before repeating the same settings with more files. The original files stay unchanged. ## Limits - Files are processed on this device. Browser memory and engine-specific limits apply. Save results before reloading. - Image replacement requires two files: subject first, background second. Local segmentation may leave edge artefacts. - Upload up to 20 files, at least 1 with a combined size of at most 100 MB. The completed output must fit within 200 MB. - Files are checked by the local engine; a matching filename alone is not proof of valid contents. - Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first. ## Questions ### Which uploaded image supplies the background? In image mode, the first file supplies the subject and the second supplies the replacement background. The replacement is fitted to the original photo dimensions, so its own edges may be cropped to fill the area. ### Does blur affect the subject? The tool blurs a copy of the original photo behind the estimated foreground. The mask aims to keep the subject sharp, but segmentation mistakes can leave blurred edges or retain small background regions around a difficult subject. ### Can this create a transparent cutout? This tool composites the estimated subject over a background treatment and exports PNG. Use Remove background when your intended result is the subject with transparent surroundings for later placement over multiple different backgrounds. ### How should I prepare a large photo? The subject photo must remain within sixteen million pixels for segmentation. Resize larger photos first, and prefer a clear, well-separated subject so the model can estimate its outline without relying on tiny ambiguous details. ### Does Blur / replace photo background upload files to another service? Processing runs in this browser, on your device. Files and pasted input are not uploaded to a conversion server. The website and required engine assets must load first; large operations depend on available device memory. ### Can I continue after changing pages? Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first. ## Related guides - [Compress image](https://localconverter.tech/compress-image.md) - [Resize image](https://localconverter.tech/resize-image.md) - [Crop & rotate image](https://localconverter.tech/crop-image.md) - [HEIC / HEIF converter](https://localconverter.tech/heic-converter.md) - [JPG to JPG](https://localconverter.tech/jpg-to-jpg.md) - [JPG to PNG](https://localconverter.tech/jpg-to-png.md)