Image Filters

Free image filters and photo adjustments

Most photos look better with a small nudge: a touch more brightness for a dim indoor shot, extra contrast and saturation for a flat landscape, a warmer tone for skin, or a black-and-white look for a portrait. The Image Filters tool gives you ten adjustment sliders — brightness, contrast, saturation, warmth, hue, blur, grayscale, sepia, invert and vignette — plus eleven one-tap looks such as Vivid, Vintage, B&W, Noir and Cool.

Every change shows up instantly in the preview, and you can press and hold the photo (or use “Show original”) to compare before and after. All processing is done with pixel maths in your browser, so it behaves the same in Chrome, Firefox, Edge and Safari, and your pictures are never uploaded.

How to use the Image Filters

1. Drop a photo on the upload area, click to choose one, or paste it with Ctrl+V.
2. Tap a look under “Looks” for a quick start. Each thumbnail previews the effect on your own photo.
3. Fine-tune with the sliders. Moving any slider switches to a custom look.
4. Press and hold the preview, or press “Show original”, to compare with the untouched photo.
5. Choose a format under “Save as” and press “Download photo” — the download is processed at full resolution.

Image Filters features

What each adjustment does

• Brightness multiplies every colour value. 120% lifts the whole picture by a fifth; pure white stays white, so pushing too far loses detail in bright areas.
• Contrast stretches values away from mid-grey (or squeezes them towards it below 100%). More contrast makes images punchier; less gives a soft, matte feel.
• Saturation controls colour intensity. 0% is fully grey, 200% is very vivid — skin tones go orange quickly, so keep portraits under about 130%.
• Warmth shifts the balance towards amber (positive) or blue (negative), like the white-balance setting on a camera.
• Hue rotate turns every colour around the colour wheel by the chosen angle — 180° swaps blues and oranges. Great for creative effects, rarely for realism.
• Blur softens the whole image; the strength scales with the photo’s size so the preview matches the download.
• Grayscale, sepia and invert blend towards black-and-white, a brown antique tone, or a photographic negative.
• Vignette darkens the corners to draw the eye to the centre.

How the filters are calculated

Saturation, hue rotation, grayscale and sepia use the colour matrices defined in the W3C Filter Effects specification — the same maths as CSS filters. Grayscale uses the Rec. 709 luminance weights (21.26% red, 71.52% green, 7.22% blue) because the eye is most sensitive to green. The colour adjustments are combined into one matrix and applied in a single pass, blur is a fast three-pass box blur that closely approximates a Gaussian, and the vignette uses a smooth radial fall-off.

Because the work is done on raw pixels rather than with the browser’s ctx.filter feature, results are identical across browsers, including Safari on iPhone and iPad.

Tips for natural-looking edits

• Start with a preset, then reduce its strength by moving sliders back towards their default values.
• Fix brightness and contrast before colour; colour judgements are easier on a well-exposed image.
• Compare often — after a few minutes of editing, eyes adapt and over-saturation starts to look normal.
• Save as PNG if you plan to edit the result again, and as JPG or WebP for sharing. The image compressor can shrink the final file further.
• Crop first with Crop Image so the vignette centres on your subject, and add a signature afterwards with Watermark Image.