DRAG SLIDER · SIDE-BY-SIDE COMPARE

Before and After Weight Loss Simulator

A weight loss simulator before and after tool puts your current photo next to an AI simulation at your goal weight — then lets you drag a slider to compare them on one frame. Upload once, see the transformation instantly.

Interactive before/after slider · Downloadable results

Upload Your Photo

Drop your photo here or browse

Full-body or portrait • JPG, PNG

Weight Change

lbs

-100 lbsLose 20 lbs+100 lbs

Body Focus

Upload a photo to start your simulation

Before

After

Demo · Upload your photo to generate your own

For visualization and motivation only

Not medical, fitness, or nutrition advice

Results may vary based on photo quality

Photos are sent to our AI provider for processing

How the before-and-after slider works

Three steps from a single upload to an interactive before and after weight loss simulator comparison.

Upload your "before" photo

Your current picture becomes the left side of every comparison — the anchor for an honest before-and-after weight loss preview.

Generate the "after" simulation

Set pounds or kilograms to lose or gain. The AI returns a photorealistic after image at that target weight.

Drag the slider to compare

Swipe the handle to reveal before vs after on one frame — the core of a weight loss simulator before and after experience.

Tips for a clearer before-and-after comparison

Better input photos make the drag slider more convincing. More capture help on our photo upload guide.

Keep the same pose

Standing straight in both frames makes the slider comparison easier to read — the AI preserves your uploaded pose.

Use consistent lighting

Even light reduces false shadows that can look like weight change when you drag the slider.

Full-body for shape, portrait for face

Torso and leg changes show in full-body before/after; upload a portrait if jaw and cheek comparison matters most.

Label your goal weight

Mental note the slider target (e.g. -25 lbs) when saving multiple before-and-after pairs from the same photo.

What you are comparing

Before

Your uploaded photo exactly as you are today — unchanged pixels on the left side of the slider.

After

An AI simulation at your chosen weight loss or gain — same identity, pose, and scene, edited body shape on the right.

Shape-focused preview? See our body shape weight loss simulator.

Why use a before-and-after simulator?

A side-by-side preview turns an abstract goal weight into something you can see and share.

Motivation wall

Save your before-and-after pair as a phone wallpaper or vision-board image while working toward a goal.

Trainer check-in

Show a coach the simulated after shape alongside your current photo — a visual target beyond scale weight.

Progress milestone preview

Before you hit -20 lbs, preview what that milestone might look like to stay focused mid-journey.

Share with accountability partners

Download the comparison to share privately with a friend or group — not medical proof, but a concrete visual goal.

Before and After Weight Loss Simulator FAQ

Questions about the comparison slider, downloads, and multiple previews.

What is a before and after weight loss simulator?

A before and after weight loss simulator takes your current photo as the "before" image, generates an AI simulation at your target weight as the "after," and lets you compare them side by side — including an interactive drag slider to reveal the transformation.

How does the weight loss simulator before and after slider work?

After generation, your original photo sits on the left and the simulated result on the right. Drag the handle horizontally to wipe between before and after on the same frame — useful for spotting subtle jaw, waist, and limb changes.

Is the before photo my real uploaded image?

Yes. The before side is your unedited upload. The after side is the AI-generated preview at the weight you selected. Both use the same pose, clothing, and background for a fair comparison.

Can I download the before and after images?

Yes. Paid results download without a watermark. Your first free preview includes a watermark on the after image; upgrade credits to save a clean before-and-after file.

Can I create multiple before-and-after pairs at different weights?

Run the simulator again with the same photo at -10, -20, or -40 lbs to build a series of comparisons and pick the goal that looks right to you.

How is this different from stitching two photos in an editor?

You only upload once. The AI produces a matched after image with consistent lighting and identity — no manual alignment, cropping, or filter matching required.

Pricing on our pricing page. Privacy in our Privacy Policy.

Create your before and after

Upload a photo above, generate your simulation, and drag the slider to compare — your weight loss simulator before and after preview in about 15 seconds.

See Pricing