The iPhone Photos app only crops rectangles and squares; there is no built-in circle mask in Apple's stock editor, so a "circle crop on iPhone" has to be done through a third-party App Store download or through a browser-based tool that runs in Safari. Circle Crop is a no-install option you can open directly in mobile Safari on any iPhone, and it produces a transparent round PNG that the iPhone Photos app itself cannot generate. You pick a JPG, PNG, or WebP file from Photos, Files, or iCloud Drive, confirm the source dimensions, and the tool cuts the largest centered square out of that image, clips it to a perfect circle, and exports the result as a full-resolution PNG with transparent corners. Everything happens in the browser tab; the file is decoded locally through a temporary object URL and is not sent to a remote server. This is the most direct way to build a profile picture, marketplace avatar, author bio headshot, or directory contact card when the destination design expects a round image, and the transparent corners let the PNG drop onto light or dark surfaces without leaving a colored square halo around the subject.
What the iPhone Photos Editor Can and Cannot Crop
Open the Photos app on your iPhone, tap Edit, and then tap the crop icon at the bottom of the screen. The editor reveals a rectangular frame, several aspect-ratio presets such as Square, 9:16, 16:9, 4:3, 3:4, and 2:3, plus rotation, straightening, flipping, and a zoom slider that lets you shrink the frame inside the image. There is no circle, ellipse, rounded rectangle, or any other non-rectangular mask inside this tool. The Save dialog also writes the result back as JPEG or HEIC, both of which lack a transparency channel, so even if you somehow pasted a circular crop into the editor it would still be saved against a solid background. That is why a workflow built around a dedicated circle cropper is necessary when the destination design wants a round image.
A few iOS workarounds come close. Markup inside the Photos app can place a colored circle on a colored background, which gives the visual impression of a round image, but the exported file is still a square image with pixels filled in around the circle. iOS Shortcuts can compose a circular PNG, but it usually requires building the shortcut yourself or installing a third-party shortcut pack. Insiders that come with iOS do not generate a transparent circle for general use. Mobile Safari, on the other hand, supports the Canvas API and PNG export, so a browser-based circle cropper can deliver a real transparent round PNG with no setup beyond opening a URL and picking a file.
How to Circle Crop on iPhone in Safari
Run the following steps on your iPhone.
- Open Safari and navigate to the Circle Crop tool.
- Tap the file picker, then choose a JPG, PNG, or WebP from Photos, Files, or iCloud Drive. The page displays the source dimensions so you can confirm the file before cropping.
- Tap Create circle crop. The tool identifies the shorter side of the image, builds an output canvas at that pixel size, and draws the largest centered square of the source clipped to a circle.
- Inspect the preview. The corners outside the circle should be transparent; if the preview shows colored corners, regenerate the crop and verify the source image is a supported format.
- Tap Download. From the share sheet, choose Save Image to add the PNG to the Photos app, or Save to Files to write it directly to iCloud Drive or On My iPhone.
- Open the saved PNG in Photos to confirm it looks round against both light and dark surfaces before you upload it as an avatar or attach it to an email signature.
What the Output Looks Like
The output is a PNG with an alpha channel that makes every pixel outside the circle fully transparent. Its dimensions are not constrained by the visible preview size on the page; the canvas always uses the natural pixel size derived from the source image's shorter side. The table below lists the exact output dimensions and the source rectangle used for several common input sizes.
| Source dimensions | Output PNG dimensions | Source rectangle used |
|---|---|---|
| 1200×800 (landscape) | 800×800 | x = 200 to x = 1000 |
| 800×1200 (portrait) | 800×800 | y = 200 to y = 1000 |
| 1000×1000 (square) | 1000×1000 | Full image |
| 1920×1080 | 1080×1080 | x = 420 to x = 1500 |
| 1500×844 | 844×844 | x = 328 to x = 1172 |
The downloaded PNG may be larger than the original JPEG or WebP file you uploaded, even though the pixel count is smaller in landscape cases. PNG uses lossless compression and carries a full alpha channel, so a 1200×800 JPEG at a few hundred kilobytes can produce an 800×800 PNG closer to three quarters of a megabyte. That is normal and not a sign of bad output; JPEG simply throws away detail to stay small, while PNG keeps every original pixel.
How the Crop Geometry Works
When the file is loaded, the tool decodes it inside the browser through a temporary local object URL and reads its width and height. The shorter side defines the side length of the output square, so the output canvas has the same pixel count on both axes. The source rectangle is centered on the original image: its starting coordinate on the longer axis is half the difference between the longer side and the shorter side, and it extends for the full shorter-side length. A circular clipping path is then applied to the output canvas with its center at half the output side and the radius equal to half the output side, which guarantees the circle is perfectly inscribed in the square.
For a 1200×800 landscape photo, the worked example is:
- Shorter side = 800 pixels
- Output canvas = 800×800
- Source rectangle starts at x = (1200 − 800) ÷ 2 = 200
- Source rectangle ends at x = 200 + 800 = 1000
- Output circle center = (400, 400); output circle radius = 400
So 800 pixels of the original landscape width land inside the circle, and 200 pixels are discarded from each side. If the subject sits in the middle of the frame, it lands cleanly inside the circle. If the subject is closer to the left or right edge, the crop will not move to keep it in frame; you have to reposition the source image first.
When to Crop or Rotate the Source First
The tool always uses the largest centered square, so it is forgiving for centered subjects and unforgiving for off-center ones. A few common iPhone scenarios that need source editing before the round crop:
- A headshot where the face sits to the left or right of the vertical center line
- A group photo where you only want one person in the avatar
- A photo taken sideways because the phone was held in the wrong orientation
- A tight crop where the chin, hat, or hair already touches the top or bottom edge
For repositioning the subject before the round mask, use Image Cropper to set a custom rectangular region that frames the subject, then return to Circle Crop on the resulting image. For sideways photos, run Image Rotator first to spin the image upright, then run the circle crop on the rotated result. For tight edges, expand the canvas of the source image before cropping, or take a new photo with more breathing room around the subject.
Inputs the Tool Accepts and Rejects
The tool accepts JPG, PNG, and WebP files with a compressed size up to 25 MiB, then enforces a second set of limits after decoding: each side must be 20,000 pixels or fewer and the total pixel count must be 40 megapixels or fewer. SVG and animated GIF are not supported because the tool is built for ordinary static bitmaps and does not preserve vector behavior or animation. The output is encoded as image/png regardless of the input format, and the output PNG does not preserve EXIF metadata, color profiles, or orientation tags from the original file.
On the iPhone specifically:
- Circle Crop accepts JPEG, PNG, and WebP only. iPhone HEIC photos need to be exported as JPEG from the Photos app first by tapping Share, then Save to Files, and choosing Image Format JPEG, before picking them in Safari.
- Photos in a supported format (JPEG, PNG, or WebP) can be picked directly from Photos or Files.
- PNG screenshots from the iPhone are accepted directly without conversion.
If the file is over 25 MiB, contains unsupported bytes, fails to decode, or trips the 40-megapixel ceiling, the page shows a clear error and clears any earlier result. The error does not block the page, so you can pick another file immediately.
Practical Tips for a Clean Round Result
A few habits produce noticeably better round crops on an iPhone:
- Hold the phone so the subject is centered in the viewfinder, with equal space on the left and right sides.
- Stand an arm's length or two from the subject so the head or object does not fill the entire frame.
- Hold the camera at eye level to keep the eyes near the vertical center of the frame.
- Shoot the photo at a square-friendly resolution, or capture a slightly wider source than you think you need so you have room to crop.
- Inspect the saved PNG against a light and a dark surface before publishing it; transparent pixels should remain transparent against both.
- Keep the original unedited source file so you can re-run the round crop if you change your mind about framing later.
Related Tools for iPhone Users
Circle Crop covers one job, which is turning a centered square into a circle, but several related tasks come up around it. For pre-editing the source image:
- Image Cropper lets you choose a custom rectangular region instead of the largest centered square.
- Image Rotator spins a sideways image by 90°, 180°, or a custom angle before the round mask.
For post-editing the round PNG:
- Add Background to PNG places the transparent circle on a solid color of your choice.
- Add Border to Image draws a thin ring around the circle.
- Round Image Corners rounds the corners of a rectangular image with a precise pixel radius for cases where a soft rectangle is acceptable.