As you can see, it seems Harper only supports English language at the time of writing this article.<\/div>\n<\/div>\n
There are also a huge list of rules that detects errors like “along time” and suggest “a long time” as the alternative. The list is huge and that’s why there is the option to search for a rule.<\/p>\n
There is no option to add your own rules though.<\/p>\nFast but how fast, rally?<\/h2>\n Harper claims to be faster than both Grammarly and LanguageTool. I don’t have data to prove it. But I cal show you this video in which I show how quickly Harper gets into action as I type.<\/p>\n\n\n
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\n <\/p><\/button>\n <\/div>\n
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\n <\/p><\/button>\n <\/p><\/button>0:00<\/span>\n\n \/
0:28<\/span>\n <\/div>\n 1\u00d7<\/button><\/button><\/p>\n <\/button><\/p>\n <\/p><\/div>\n<\/div>\n<\/div>\n<\/figure>\n
Since the processing is local, the suggestions are pretty fast actually.<\/p>\n
Harper is not perfect, of course<\/h2>\n For example, here I deliberately mistyped “video in” as “videoin” and Harper didn’t suggest it as one of the possible correct options.<\/p>\n
And I think it limits itself to suggest maximum three suggestions or the most it can fit in a line. <\/p>\nHarper offers limited suggestions<\/span><\/figcaption><\/figure>\nAnother thing is that Harper is not as intelligent as I would want it to be. I am an excellent tester for grammar tools. I make so many mistakes and on so many levels that even the best grammar checkers throw in the towel.<\/p>\n
That’s why I tested Harper against LanguageTool with a sentence with multiple grammatical issues.<\/p>\n
Harper was primarily so focused on the spelling of Wikimedia and Cloudflare that it forgot to point out other grammatical mistakes. <\/p>\nThe weird thing is that both Cloudflare and Wikimedia were correctly spelled. Usually, Harper is good at recognizing brand names, except in this case where it made two false positives in a single sentence.<\/p>\n
On the other hand, LanguageTool did indicate that there are some grammatical mistakes worth looking for.<\/p>\nNeither could correct the sentence entirely, as the correct sentence I was aiming for was:<\/p>\n
Grammarly, LanguageTool, and Cloudflare went to a bar run by Wikimedia but it was closed, so they went to Wikipedia. <\/p><\/blockquote>\n
Yeah! I know. No AI can guess what goes in my mind when I make these typos. It takes real intelligence to deal with such stupidity \ud83d\ude1c<\/p>\n
At least in Ghost, the CMS I use to publish content on It’s FOSS, sometime the suggestions tooltip wouldn’t close until I start typing something. It’s minor but annoying.<\/p>\n
Conclusion<\/h2>\n Both Grammarly and LanguageTool have evolved to writing assistant with AI features. <\/p>\n
But here’s the thing. Sometime simplicity is the best feature you look for. Not everyone is a professional writer looking for additional features to improve their work.<\/p>\n
For a casual user, a no-fluff, simple grammar checker is more than sufficient to save them from embarrassing typos and grammatical mistakes in their emails.<\/p>\n
And Harper is an excellent choice at that. It is definitely better than your browser’s built-in spell checker, it is an open source software<\/a> and it processes your data locally. <\/p>\nIf you are not dependent on a more professional tool like LanguageTool or Grammarly, you should definitely ‘upgrade’ to Harper.<\/p>","protected":false},"excerpt":{"rendered":"
When it comes to grammar checking, Grammarly is the premium tool for it. It’s a proprietary tool and it was among the first one to make a mark as a…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rop_custom_images_group":[],"rop_custom_messages_group":[],"rop_publish_now":"initial","rop_publish_now_accounts":[],"rop_publish_now_history":[],"rop_publish_now_status":"pending","footnotes":""},"categories":[1],"tags":[],"class_list":["post-1544","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-rss"],"_links":{"self":[{"href":"https:\/\/catbradley.io\/index.php?rest_route=\/wp\/v2\/posts\/1544","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/catbradley.io\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/catbradley.io\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/catbradley.io\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/catbradley.io\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1544"}],"version-history":[{"count":0,"href":"https:\/\/catbradley.io\/index.php?rest_route=\/wp\/v2\/posts\/1544\/revisions"}],"wp:attachment":[{"href":"https:\/\/catbradley.io\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1544"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/catbradley.io\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1544"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/catbradley.io\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1544"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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![\"I](\"https:\/\/itsfoss.com\/content\/images\/2025\/07\/Harper-rules.png\")
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