How to Swap Faces in a Photo — and When You Shouldn't
By the NextG Design team · Published 19 October 2026 · 3 min read
Quick answer: To swap faces realistically, use two photos where the faces point the same way and are lit from a similar direction, at similar resolution. A face-swap tool maps hundreds of landmarks on both faces, warps the source face onto the target's shape and expression, then matches skin tone and lighting at the edges. Only swap faces of people who have agreed, never use it to impersonate, deceive or harass anyone, and label the result as edited when you share it.
How face swapping works
Modern face swaps start with face landmarks: a model finds hundreds of points on each face — eye corners, nostrils, lip edges, jaw line. The NextG Design editor uses Google's MediaPipe face mesh with 468 points. The two meshes are triangulated, and each triangle of the source face is warped onto the matching triangle of the target face, so the new face takes on the target's head shape and expression. Finally the colours are matched: overall skin tone first, then a smooth correction that makes the edges of the new face meet the target photo exactly. The swap goes on its own layer.
Getting a realistic result
- Same angle. Two front-facing photos, or two that turn the same way. When one head is turned three-quarters, the hidden side can't be filled from the other photo and the tool leaves the target's own skin there.
- Similar light. A face lit from the left pasted into a scene lit from the right never looks right, however good the colour match.
- Similar sharpness. Use the sharper photo as the source or soften the swapped layer slightly to match.
- Neutral expressions are easiest; wide smiles and open mouths are harder.
- Finish by hand: lower the layer's opacity a touch, or paint on its mask to blend the forehead and chin.
Consent, law and ethics
Face swapping is fun for birthday cards, group photos where someone blinked, or putting yourself in a movie-style poster. It becomes harmful when it's used without permission. Follow these rules:
- Get consent from the people in both photos — and from a parent or guardian for children.
- Never create sexual, humiliating or defamatory images of real people. In many countries, including the UK, Australia, much of the EU and many US states, creating or sharing non-consensual intimate or deceptive deepfakes is a crime.
- Don't impersonate anyone for fraud, scams or misinformation.
- Label edits when you share them, especially anything that could be mistaken for a real event.
The NextG Design Face Swap asks you to confirm permission before it will swap.
Why on-device face swapping is more private
A face is biometric data. Many face-swap apps upload photos to their servers, where they may be stored or used for training. The NextG Design editor detects faces and swaps them entirely in your browser — no photo or face data is sent anywhere, and nothing is kept after you close the tab. See our guide to on-device vs cloud AI photo editing.
Frequently asked questions
Is this face swap free?
Yes. It's free, has no watermark, and runs on your device using a small face-landmark model.
Are the photos uploaded?
No. Face detection and swapping happen in your browser; neither photo leaves your device.
Why does my face swap look patchy?
Usually the faces point in different directions or are lit differently. Use two photos with matching head angles and similar lighting.
Can I swap several faces at once?
Yes. Choose the source face, then click every face you want to replace in the target photo.
Is face swapping legal?
Swapping faces with consent for personal, creative or humorous use is generally legal. Creating sexual, defamatory or deceptive images of real people without consent is illegal in many places and always harmful.
Try it free: the Face Swap runs entirely in your browser — no upload, no account, no watermark.