Available on iPhone
Put a card or your phone next to the object and take a photo. Then draw lines for length and rectangles for area — right on the picture.
Free to try · Pro Lifetime is one payment — no subscription.
Use cases
Shipping & packaging
Online selling
Home & DIY
Interior design
Field notes
How it works
Take or pick a photo with an object of known size next to what you want to measure — a credit card or your iPhone works great.
Pick the reference from the presets and drag its frame onto its edges. Photo taken at an angle? Place a point on each of its 4 corners.
Tap + to add a line or a rectangle. RefScale shows length, width, height, and area in mm, cm, inches, or feet.
What people measure
Every line and rectangle stays on the picture with its label, ready to share.
A parcel
Width and length before you book shipping.
A piece of fabric
One rectangle gives both sides and the area.
A T-shirt
Chest and length, labeled for a listing.
A box shot at an angle
Mark the card's 4 corners, then measure.
Lines and rectangles
Tap + to add either one. A rectangle shows its width, its height, and the area inside, in cm², m², in², or ft². Name each measurement — "Chest", "Width" — so the photo explains itself.
Zoom in to put every point on the edge you mean.
Photos at an angle
Place a point on each corner of the card instead of a frame. RefScale takes the angle of the photo into account for things lying on the same flat surface as the card.
Handy for a box on a table or a rug on the floor.
Why it works
A camera doesn't know how big anything is — until something in the photo does. Include a credit card, an iPhone, or any object with known dimensions, and RefScale uses it to set the scale.
Every other measurement in the frame falls into place from there.
Accuracy
RefScale measurements are estimates. These four habits make the biggest difference:
Place the reference right next to the object you measure.
Both objects should sit on the same plane, at the same distance from the camera.
Hold the camera parallel to the surface. If you can't, mark the reference by its 4 corners.
Put markers exactly on the edges — a few pixels matter on small objects.
RefScale is made for everyday sizing, not for certified, construction-grade, or safety-critical measurements.
Everything else
Payment cards and iPhone models are built in — or save your own custom reference size.
Switch units instantly. Every measurement on the photo updates in real time.
Take a photo right in the app, choose one from your library, or paste an image you copied.
Give each measurement a name and notes, then find it again with search.
Pro: share the photo and every measurement as a tidy PDF page.
Open the app and start measuring. Purchases and restore work without registration.
Pricing
Free
$0
Pro Lifetime
One-time$9.99
Pay once. No subscription.
Price shown in USD. Local prices on the App Store may vary by country or region.
Pay once, keep it
One payment unlocks unlimited measurements for good — no monthly or yearly fee.
Nothing to cancel
No renewals to keep track of and no surprise charges.
On all your iPhones
Restore Pro Lifetime on your devices with the same Apple Account.
FAQ
You include an object of known size in the photo, such as a credit card (85.60 × 53.98 mm) or a supported iPhone model. RefScale uses that reference to set the scale, then converts every line you draw into a length and every rectangle into its sides and area.
Measurements are estimates, and the result depends on the photo and on where you place the points. It helps to keep the reference next to the object on the same flat surface, take the photo straight on (or mark the reference by its 4 corners), and zoom in to place points.
No. You can try RefScale with 1 free measurement. To measure without limits, unlock Pro Lifetime with a single one-time purchase — there is no monthly or yearly fee.
No. RefScale works from a normal photo, so it runs on any iPhone with iOS 18.6 or later. Choose any photo from your library — including ones taken earlier — or paste an image from the clipboard.
Any object with known dimensions: a payment card, a supported iPhone model, or a custom reference size you enter yourself. You can save custom references to reuse them.
Lengths with a line and areas with a rectangle: parcels, fabric, clothes, furniture, prints, rugs, and everyday items. Things lying on the same flat surface as the reference work best.
Yes. Instead of a frame, place a point on each of the reference's 4 corners. RefScale then takes the angle into account for things on the same flat surface as the reference.
No. Measuring happens on your iPhone and your photos stay on your device. RefScale does not require an account or sign-in.
Millimeters, centimeters, inches, and feet/inches. Switch units at any time — every measurement on the photo updates instantly.
Yes. Share the annotated photo with every label to Messages, Mail, or any app that accepts images. Free shares carry a small RefScale watermark; Pro adds full-resolution exports without it and a PDF report.
Free to download. No account required to get started.
Download on the App Store