How to Crop Your AI Headshot for Bluesky and Mastodon
Your profile picture is a tiny first impression. Use these exact cropping rules to make sure your face, not your shirt, is the star. Get the framing right in one try.
Why Bluesky and Mastodon Need Different Crops
Think of your profile picture as your digital handshake. On Bluesky, that handshake happens in a tiny, tight circle. On Mastodon, it’s a slightly roomier oval. Use the same square file for both, and you’ll lose your shoulders on one platform and get your forehead chopped on the other. I’ve watched clients post the same image everywhere, only to see their perfectly framed shot on LinkedIn become a disembodied floating head on Bluesky. The platforms fight your photo, and your photo loses.
Why does this happen? Each network uses a different shape mask. Bluesky’s circle is aggressive, cutting off everything outside its perfect ring. Mastodon’s oval is more forgiving vertically but will still clip the sides of a square. If you don’t crop with these final shapes in mind, the algorithm will decide what part of you gets seen. You don’t want an algorithm picking your best side.
The Exact Crop Measurements to Use
Start with a square. Always. Your source image should be at least 2000 pixels wide and tall. From that square, you will create two custom crops.
For Bluesky’s circle, crop to a 1:1 ratio, but position your face high. Imagine a box 1000 pixels by 1000 pixels. Your head and the top of your shoulders should fill about 70% of that box. Leave generous space above your hair. This feels wrong when you’re looking at the square, but trust the process. The circle will hug the sides, so that empty top space keeps your eyes in the upper third.
For Mastodon’s oval, use a 4:5 vertical rectangle. A 1200 pixel width by 1500 pixel height is perfect. This shape gives the oval room to breathe. You can include more of your shoulders here, maybe even a hint of a collar or a necklace. The oval will softly fade at the edges, so you have a bit more compositional freedom.
Position Your Eyes in the Frame
Where should your eyes go? This is the single most important placement choice. Your eyes are the anchor. For both crops, position them in the upper half of the frame. A good rule is to place the pupil line about 60% down from the top of the image. Not the center. Never the center.
I once shot a headshot for a brilliant engineer who kept slouching his chin down, thinking it looked more thoughtful. In the raw files, his eyes were dead center. When we cropped for Bluesky, the circle cut off his forehead and gave him a strange, cramped intensity. We reshoot, I had him sit up straight and look at a spot just above my lens. That tiny shift placed his eyes higher. The final crop made him look engaged and open, not like he was staring up from a well.
Check this: can you draw a slight smiley curve from eye to eye? That curve should sit comfortably in the top half of your frame. If it’s bisected by the midline, you’re too low.
The Most Common Mistake: Cropping Too Low
Everyone does this. You open your photo, zoom in on your face because you’re worried about a blemish or a stray hair, and you crop tight to your chin. This is a disaster for social crops. Why? Because the platform’s shape will then amputate your jawline. You become a talking forehead with eyes.
Always include the space above your head. I call it “sky for your hair.” In your square crop, there should be a clear gap between the top of your hair and the edge of the image. This gap is your safety buffer. It ensures the circular mask doesn’t scalp you. When you think you’ve left enough room, add 10% more. Your future self, viewing your profile on a phone, will thank you.
What’s the quickest way to check your work? Flip the image upside down. Seriously. This trick breaks your brain’s attachment to your own face and lets you see the composition as pure shapes. Is the largest dark mass (your hair) crammed against the top edge? If so, you’ve cropped too low.
Upload and Check Your Work on Mobile
Your desktop preview lies. You must look at the image on the device where 90% of people will see it: a phone. After you crop, send the files to your phone. Upload them to a private post or your profile, and then step back. Literally. Hold the phone at arm’s length, the way you’d casually scroll.
Does your face read instantly? Or do you have to squint? At that distance, your head should be clearly recognizable without any zoom. The background should be simple, not fighting for attention. I’ve seen gorgeous, detailed photos become a muddy blur at thumbnail size because the pattern on a blazer turned into noisy static.
Check both the light and dark mode of the app. A white background on your photo might vanish in light mode, changing your silhouette. A dark jacket might disappear in dark mode. You need enough contrast around the edges so your shape remains defined in any setting.
Great profile photos aren't taken, they're made—in the final crop. Give your face the right space to live within these strange little shapes, and that digital handshake will always feel firm, friendly, and unmistakably you.
Where this stops short, Keep Your Face Real: Subtle Retouch for Bright Portraze Headshots picks the thread up.