As you can see in the screenshot above, there is a small counter at the bottom right corner of the text box that counts down the characters as you type them. This means that the maximum number of characters allowed per translation is set at 5,000. We’re not sure why Google has implemented a limit, but basically it will now make it more tedious for people who might be trying to translate longer documents.
Note that this limitation does not seem to apply to websites that might contain more than 5,000 characters, but at the same time Google Translate’s API does have the same limits, so there is some discrepancy going on here. Also the translation card from Google Search is also limited to 2,800 characters.
In any case guess Google has their own reasons, but basically if you’re looking to translate bigger batches of text using Google Translate, you’ll have to work slower now or open up multiple windows or find a different translation service.