You can view data across different browsers at Can I Use. However this information tends to confuse people as it looks as though IE is the only browser with support. Read on to understand the status of Grid Layout in browsers.
Grid is under development in browsers, this development is typically happening behind a browser flag or in an experimental version of the browser. This prevents incomplete or experimental parts of the specification being used in production by web developers.
Due to the experimental nature of this sometimes examples will not work in one browser or another. Please don’t email me to complain that Firefox Nightlies look different to Chrome Canary! I have linked to the meta bugs below for each browser so if you need to know exactly why one is different to another, take a look at those. This is the way of experimental features.
If you find a bug in a browser implementation then the best thing to do is to search the logged bugs for that browser as this will include known bugs and issues still being worked on. If you have found something new then you can find information about logging bugs with browsers here.
On launch Edge shipped with the IE11 Grid implementation. Therefore the current implementation in Edge is against the original and not the new spec. In September 2015 Microsoft indicated that updating Grid to the current spec is on the backlog with a priority of High.
The original Grid implementation was part of IE10, also in IE11. This implementation is now quite different to the current spec and other implementations.
Igalia have posted the Intent to Ship for Grid into Chrome. This means that it could be enabled by default (no browser flag required) as soon as March 2017.
My reference implementation is the one in Blink, unless stated otherwise on an example. I am typically using Chrome and Chrome Canary.
The Blink implementation has been carried out by Igalia, sponsored by Bloomberg. You can read about the implementation work in this post from Igalia.
At the present time you need to enable the Experimental Web Platform Features Flag in Chrome or Opera.
Download Chrome Canary if you want to get the very latest features that have been implemented. Chrome Canary does not need flags enabled.
For Safari Technology Preview turn Grid support on in the Develop Menu under Experimental Features.
This implementation is also by Igalia but lags slightly behind the Chrome one. Note that Grid being present in Safari Technology Preview does not mean it will be in the next version of Safari.
Firefox have indicated they intend to ship Grid in March.
Grid is currently being implemented in Gecko. You need to enable the layout.css.grid.enabled flag by going to about:config in regular Firefox or Developer Edition. For the latest features download a Firefox Nightly or the Firefox Developer Edition. In Nightly you do not need to enable the flag - Grid should just work!
If you are using Firefox then you can use the experimental CSS Grid Inspector to help you visualize your grids. It is a tool in development - just like Grid Layout.
Firefox Nightlies and Firefox Developer Edition also include a grid highlighter in DevTools.