Type a number once and see it in every unit at the same time. Over 800 units and 160+ currencies with daily rates, and no ads or accounts to get in your way.
Units is the fast, friendly unit converter. Type a number into any unit and instantly see it in every other one, all on a single screen. There's no picking what to convert from and to, no digging through menus, and no ads.
With more than 800 units across 43 categories, Units covers everyday conversions like length, weight, volume and temperature, and the ones you need less often, from torque and fuel consumption to data rates, shoe sizes and musical notes.
SEE EVERYTHING AT ONCE
• Enter a value in any unit and every other unit in the category updates as you type
• A keypad made for numbers, so the decimal point is always right where you need it
CURRENCY
• Convert between more than 160 currencies
• Exchange rates updated every day
MAKE IT YOURS
• Hide the units you never use, so the ones you need are always in view
• Reorder units and categories so your favorites come first
• Switch on a two-column layout to see even more at a glance
• Leave a tip to unlock a collection of alternative app icons
MADE FOR YOUR DEVICES
• Designed for iPhone and iPad, with your categories and conversion side by side on larger screens
• Makes full use of iPhone Duo, whether it's open or closed
• Handoff picks up a conversion where you left off on another device
• Supports Dark Mode and Dynamic Type
Units has been converting since 2008, and is lovingly made in Scotland.
I recently did extensive traveling and the currency conversion tool was invaluable. However, many times when I went back into it, the main screen with all conversions displayed and I had to go back into currency. A feature to keep a particular conversion open or create a specific widget to access such would be really helpful.
I like it but could use another liquid volume unit
Nerd of Rocks
Hello! I’m writing this from the US, where we have weird units (I know, I know). Is there any way you could add the unit “acre-feet” to your liquid volume list? I work in water resources in the Desert Southwest and we regularly use acre-feet for calculating water pumping volumes for regulatory compliance. It’s an annoying unit but it’s way we’ve got here, where we seem to actively fear the metric system. Sigh.
I love this app
Dex Red
I’ve had it on my phone for as long as I can remember and it has served me well over the years. Having a converter app that works without needing an internet browser or data connection is insanely handy in all types of situations. Recent updates have only made the app even better (I’m a sucker for a good dark mode).
Please bring back ruler!
Undfeatable
Have been using this app for nearly as long as it’s been out. Primarily as a ruler. Even though it was stuck in the old sizing, really liked that function. I know it must be difficult to address all the screen sizes now, but will definitely tip when that’s restored.
NEW:
• Units now makes full use of iPhone Duo: the inner display shows your categories and conversion side by side, and no field sits in the hinge when it's folded.
• App icons have been redrawn for iOS 26, with Liquid Glass, dark, and tinted versions. And added some new custom icons.
• The keypad now taps back with haptics as you type, and holding backspace keeps deleting.
• Long-press a converted value to copy it, with or without its unit.
• Unit information now opens in a small popover instead of an alert.
• Improved feel of unit editing and settings screens with some haptics and animations.
• Clearing a value now fades the other results out smoothly.
• The currency Last Updated label now shows it can be tapped to update, with a spinner while it updates and a tap of haptic feedback when it's done.
FIXED:
• Currencies you turn on soon after installing Units no longer switch themselves off again when new exchange rates arrive.
• If you've used Units since its early days, Luminance now keeps its place in the category list instead of dropping to the bottom.
• Continuing a conversion on another device with Handoff now keeps the value when you customise the units, and clearing a conversion no longer hands off the old value.
• The currency screen’s “Last Updated” time reads more naturally, says “just now” for the first minute, and no longer shows a raw date if your clock has changed.
• Fixed a rare crash after entering a thousand or so different values, and a crash when editing results that have spaces between the digits, as in French.
• Men's shoe sizes now match standard size charts: European sizes were a size small, and Japanese sizes from UK 10 up were half a size large. Women's sizes also convert back and forth consistently.
• Numbers are now read the way your region writes them, including a comma as the decimal point and other minus signs. The keypad's decimal key now types your region's decimal point, so a "." in Germany, for example, is read as a thousands separator.
• Opening Units without an internet connection no longer throws away the latest downloaded currency rates.
• Wavelength units in Electromagnetic Radiation, and siemens-based units in Electrical Resistance & Conductance, now convert correctly instead of showing 0 or ∞.
• Typing a value to convert is snappier, especially in categories with lots of units like Length.
• Fixed a possible crash when currency rates finish updating while the category list or Currency screen is in use.
• If currency rates have never downloaded, opening Currency now tries again.
• Pasting or typing an incomplete value, like "2+" or "1.2.3", now converts the number at the start instead of 0.
Version 3.1
The developer, Homegrown Software Ltd, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
Identifiers
Usage Data
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Homegrown Software Ltd
Size
89.7 MB
Category
Utilities
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
iPad Requires iPadOS 17.0 or later.
Mac Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
