Ink, short for Interface Kit, is an HTML5 and CSS3 framework built at SAPO, the Portuguese web portal, for fast website design and prototyping. It still loads: the Ink homepage offers version 3.1.10 under the MIT licence, with a responsive grid, Sass variables for breakpoints and colours, and a modular JavaScript library loaded through Ink.requireModules. But nothing new has shipped in a decade. The Ink release history ends with 3.1.10 on August 6, 2015, and the GitHub repository's last push was on January 31, 2022.
That leaves Ink sites on code that predates CSS Grid in browsers and gets no security or compatibility fixes. The picks below all cover Ink's core job, a grid plus ready-made interface pieces, and are ordered from the closest match to the lightest. For a minimal stylesheet in the spirit of Ink's small footprint, see our Pure CSS alternatives roundup.
Prices below are as of November 8, 2026. Our method is on How we review tools.
Quick comparison
| Tool | Best for | Price | Platforms |
|---|---|---|---|
| Bootstrap | Grid plus JavaScript components | Free (MIT) | Any stack; Sass for theming |
| Foundation | Ink-like grid class naming | Free (MIT) | Any stack; jQuery for plugins |
| UIkit | Modular CSS and JS without dependencies | Free (MIT) | Any stack; Less or Sass |
| Fomantic-UI | Large component set with themes | Free (MIT) | Any stack; jQuery 3.4+ |
| Bulma | Readable CSS-only components | Free (MIT) | Any stack; Dart Sass |
| Tailwind CSS | Fast prototyping with utilities | Free (MIT) | Chrome 111, Safari 16.4, Firefox 128+ |
| Pico CSS | Styled HTML with almost no classes | Free (MIT) | Any stack |
Bootstrap
Bootstrap covers the same ground Ink did, a responsive grid plus JavaScript for modals, dropdowns, tabs and carousels, and it is still actively developed. Ink's percentage classes such as all-50 and small-100 translate to Bootstrap's 12-column classes such as col-12 col-md-6, with breakpoints at 576, 768, 992, 1200 and 1400 pixels.
The stable line is 5.3.8 from August 26, 2025. It drops jQuery and needs only Popper for positioned elements. Version 6.0.0-alpha.1 followed on October 8, 2026 with ESM-only plugins and prefix-style classes such as .md:d-none.
Best for: Ink sites that use both the grid and the JavaScript components and want a long-term home.
Pricing:
- Free, MIT licence
- No paid tier
Watch out for:
- A move now means a second migration later. The Bootstrap 6 alpha post renames responsive classes and removes the window.bootstrap global, although v5 remains supported and 5.4.0 is due before any end-of-life date is announced.
Official site: Bootstrap. Our listing: Bootstrap.
Foundation
Foundation feels most familiar to Ink developers because its grid speaks the same size-first language. The XY Grid uses .grid-x and .cell with classes such as small-12 medium-6 large-4, so an Ink layout built on small-100 and medium-50 maps over almost line for line. Foundation 6.9.0, from September 27, 2024, is MIT-licensed and also ships JavaScript plugins for menus, reveal modals and tabs.
Those plugins depend on jQuery 3.6 or newer plus motion-ui and what-input. The project's next step is Yeti, a zero-build stylesheet that reached 7.0.0-alpha.2 on npm on November 4, 2026.
Best for: Teams who want the shortest path from Ink's grid classes and are comfortable with jQuery.
Pricing:
- Foundation 6: free, MIT licence
- Yeti: free under FSL-1.1-MIT, which becomes MIT after two years
Watch out for:
- Foundation 6 is near the end of its road. The September 2026 Yeti announcement calls 6.9.0 the final planned feature release, with only bug fixes on the v6 branch.
- Yeti is still alpha and uses a source-available licence for its first two years, which some companies' open source policies do not allow.
Official site: Foundation. Our listing: Foundation.
UIkit
UIkit matches Ink's modular approach: pick the components you need and leave the rest out. The official site lists 81 components, and the JavaScript has no dependencies, so there is no jQuery or Popper to load alongside it. Theming works through Less or Sass, much as Ink exposed its settings as Sass variables.
Version 3.25.29 shipped on November 2, 2026, MIT-licensed, with 3.25.30 development builds published the next day. YOOtheme, the German company behind it, keeps a steady release rhythm.
Best for: Sites that want Ink-style modules for sliders, modals and navigation in one kit.
Pricing:
- Framework: free, MIT licence
- YOOtheme Pro page builder: Standard €129/year (3 sites), Developer €329/year, Agency €529/year
Watch out for:
- Bug reports pile up. The UIkit GitHub repository shows 575 open issues, and YOOtheme's paid work centres on its WordPress and Joomla builder.
Official site: UIkit.
Fomantic-UI
Fomantic-UI is the official community fork of Semantic UI, and it offers the widest component set here: 60+ components, 250+ variations and 5,000+ theming variables. Class names read like plain English, such as ui primary button or ui three column grid, which makes old Ink templates easy to rewrite by eye.
The stable release is 2.9.4 from February 23, 2025, MIT-licensed. Nightly builds keep coming, with 2.10.0-beta.129 published on November 4, 2026, and version 3 development has started.
Best for: Internal apps and dashboards that need many prebuilt widgets and theme variants.
Pricing:
- Free, MIT licence
Watch out for:
- It runs on jQuery and a gulp and Less build. The 2.9.4 package on the Fomantic-UI npm page depends on jquery ^3.4.0, gulp and less.
- The last stable release is from early 2025, so fixes since then are only in nightly builds.
Official site: Fomantic-UI.
Bulma
Bulma replaces Ink's CSS side and nothing else. It is a pure CSS framework with Flexbox columns, a CSS Grid layer, dark mode and CSS variables, and its class names such as columns, is-half and is-mobile are easy to read in templates.
The latest release is 1.0.4 from April 19, 2025, under MIT. Customization runs through Dart Sass, which suits teams who already edited Ink's Sass variables.
Best for: Server-rendered sites that used Ink mostly for layout and typography.
Pricing:
- Free, MIT licence
- Funded by Patreon and GitHub sponsors
Watch out for:
- Every interactive piece needs your own JavaScript, including the mobile menu toggle.
- The full build is heavy for a CSS-only kit. The Bulma npm package ships css/bulma.min.css at about 678 KB, roughly 65 KB gzipped, so import only the Sass modules you use.
Official site: Bulma.
Tailwind CSS
Ink was sold on prototyping speed, and Tailwind is where most front-end prototyping happens now. Instead of components you compose utilities such as grid, md:grid-cols-2 and p-4, and the default breakpoints sit at 40rem, 48rem, 64rem, 80rem and 96rem. For a quick mockup with no build step, @tailwindcss/browser loads it from a script tag.
Tailwind 4.3.5 was published on November 6, 2026 under MIT. The framework is free; Tailwind Plus, the paid set of templates and UI blocks, is sold separately.
Best for: Teams who want custom designs and fast iteration rather than a fixed component look.
Pricing:
- Framework: free, MIT licence
- Tailwind Plus: one-time purchase with lifetime access (no subscription)
Watch out for:
- Older browsers are out. The Tailwind compatibility notes list Chrome 111, Safari 16.4 and Firefox 128 as the minimum for v4.
- There are no ready-made widgets in the free framework, so Ink's modals and tabs need another library or your own code.
Official site: Tailwind CSS. Our listing: Tailwind CSS.
Pico CSS
Pico is the lightest swap on the list. It styles semantic HTML elements directly, so a form, table or nav looks finished with no classes, and a class-less build goes further still. Twenty precompiled colour themes cover light and dark mode.
Version 2.1.1, from March 15, 2025, is the current release, MIT-licensed. Its .grid class gives a single column on phones and equal columns from 768 pixels up.
Best for: Small sites and prototypes where Ink's full kit was more than you used.
Pricing:
- Free, MIT licence
Watch out for:
- No JavaScript ships with it. The Pico modal page says you implement your own script to open and close dialogs.
Official site: Pico CSS.
How to choose
| If you need | Pick |
|---|---|
| Grid and JavaScript components with long-term support | Bootstrap |
| Grid classes that read like Ink's | Foundation |
| Modular components with no jQuery | UIkit |
| The biggest set of prebuilt widgets | Fomantic-UI |
| CSS-only layout and typography | Bulma |
| Custom designs and quick mockups | Tailwind CSS |
| One stylesheet, almost no classes | Pico CSS |
When to stay with Ink
Leave Ink in place only on a static or internal site that you will not touch again. The files still download from the Ink GitHub repository under MIT, but no release has shipped since 2015, so any bug in the JavaScript or a layout problem in a new browser is yours to fix. For anything you still develop, plan the move.
Frequently asked questions
Is the SAPO Ink framework still maintained?
No. Ink 3.1.10 from August 6, 2015 is the final release, and the repository has had no push since January 31, 2022. The homepage at ink.sapo.pt still serves the 3.1.10 docs and downloads.
Is this the same Ink as the React library for command-line apps?
No. The ink package on npm is a separate project that renders React components in the terminal, and it is very much alive: ink on npm reached 8.0.0 on October 3, 2026 and needs Node 22 or newer. It has nothing to do with web page styling.
What about ink, the scripting language from inkle?
That ink is a narrative scripting language for branching stories, used in inkle's own games such as 80 Days and Heaven's Vault. It is MIT-licensed, comes with the Inky editor for Mac, Windows and Linux, and plugs into Unity, with an Unreal integration called Inkpot from The Chinese Room. The inkle ink page has the downloads.
What is the easiest way to replace Ink's grid?
For a like-for-like swap, use Foundation's XY Grid, whose small-, medium- and large- classes mirror Ink's naming. For new work, native CSS Grid with a few media queries does the job without a framework, and Bootstrap or Pico add one when you want ready-made defaults.
