SDWebImage vs YYKit
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
Loads, caches and displays web images on Apple platforms, with a UIImageView-style API.
Open source · MIT
A large collection of iOS UI and utility components bundled into one library.
The short answer
Choose SDWebImage if you need…
- iOS or macOS app developers who need to show remote images in lists or grids
- Teams that want caching, progressive loading and image transformations handled by a tested library
- Developers building SwiftUI apps who want to use the separate SDWebImageSwiftUI module built on this core
Choose YYKit if you need…
- iOS developers maintaining Objective-C codebases
- Developers who need a specific component such as rich text or image decoding
- Teams that want to borrow ideas from a mature, widely starred iOS codebase
Side-by-side
| SDWebImage | YYKit | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 25.6k | 14k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | Objective-C | Objective-C |
| Last code update | 7 months ago | 2 years ago |
What each one is
SDWebImage
SDWebImage is an Objective-C library for Apple platforms that downloads images from URLs asynchronously and keeps them in memory and on disk so they do not need to be fetched again. It adds helper methods to UI elements such as UIImageView, UIButton and MKAnnotationView so app developers can show a web image with a single call. It also supports animated images like GIF and APNG, and can be extended with plugins for other formats.
YYKit
YYKit is an umbrella collection of iOS components written in Objective-C, covering areas such as models, caching, images, rich text, and utility categories. The author split its parts into separate smaller libraries, which the README recommends using instead of the combined YYKit package. It is aimed at iOS developers who want ready-made building blocks for their apps.
Best for
SDWebImage
- iOS or macOS app developers who need to show remote images in lists or grids
- Teams that want caching, progressive loading and image transformations handled by a tested library
- Developers building SwiftUI apps who want to use the separate SDWebImageSwiftUI module built on this core
YYKit
- iOS developers maintaining Objective-C codebases
- Developers who need a specific component such as rich text or image decoding
- Teams that want to borrow ideas from a mature, widely starred iOS codebase
Strengths
SDWebImage
- Widely used, with about 25,600 GitHub stars and an active push date in April 2026
- Covers downloading, memory and disk caching, and background decoding in one package
- Modular design with separate plugins for extra formats and SwiftUI
YYKit
- Broad coverage of common iOS needs in one collection
- Installable through CocoaPods, Carthage, or manual source copying
- Released under the permissive MIT license
Not ideal for
SDWebImage
- Developers working only with Android, web browsers or other non-Apple platforms, since the library targets Apple platforms
- Beginners with no Xcode or Apple-platform experience, since integration assumes familiarity with app development
- Projects needing modern animated formats such as animated WebP or HEIC by default, since the README says these must be registered manually
YYKit
- Developers starting a new project who want Swift-first libraries, since the README describes Objective-C components only
- Anyone targeting platforms other than iOS, because the README describes iOS components only
- Projects that need a current iOS version: the README lists iOS 6.0+ and Xcode 8.0+, which are very old
Trade-offs
SDWebImage
- Only for Apple platforms; the README does not cover other ecosystems
- Many advanced features are documented in an external wiki, so the README alone gives limited detail
- Some formats such as animated WebP need manual registration, and visionOS support is described as beta for some versions
YYKit
- The README says the author does not recommend using the combined YYKit directly, pointing users to the split components instead
- Minimum supported versions (iOS 6.0, Xcode 8.0) are very old, so compatibility with current toolchains is unclear from the README
- Category methods have no prefix, which the README itself warns may cause conflicts
Getting started
SDWebImage
Clone the repository
git clone https://github.com/SDWebImage/SDWebImageYYKit
Add to Podfile, then install (CocoaPods)
pod 'YYKit'Install pods
pod installFrequently asked questions
What is the difference between SDWebImage and YYKit?
SDWebImage: Loads, caches and displays web images on Apple platforms, with a UIImageView-style API. YYKit: A large collection of iOS UI and utility components bundled into one library. SDWebImage suits ios or macos app developers who need to show remote images in lists or grids, while YYKit suits ios developers maintaining objective-c codebases.
Are SDWebImage and YYKit free?
SDWebImage: Free and open source. YYKit: Free and open source.
Is SDWebImage or YYKit more popular?
SDWebImage has more GitHub stars (25.6k) than YYKit (14k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to SDWebImage and YYKit?
Other options people compare them with include Kingfisher, SVProgressHUD, FSCalendar, IGListKit.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.