Read this article if...
you’ve ever wondered which tool deserves the title of the best plagiarism checker. I’ve tested a bunch of options, and trust me, there’s a lot you might not expect!
If you care about originality or want to make sure your work doesn’t get flagged, this guide is for you.
I’ll walk you through AIDetectPlus, Grammarly, Ithenticate, Unicheck, Scribbr, Quetext, Duplichecker, and Copyscape.
Ever heard someone rave about a tool, but you weren’t sure if it was worth it? I’ll spill the tea on what actually makes each checker stand out (or flop!).
This isn’t just a list—I share my own experiences and frustrations, so you’re not left wasting time or money on the duds.
If you skip this, you might miss out on features that save you from embarrassing or expensive slip-ups.
Stick around because I promise by the end, you’ll know which tool truly fits your needs—and which one I’d pick for myself.
Here’s a quick table of contents for you to jump right to what you need:
- 8 Best Plagiarism Checkers (Table)
- #1 - AIDetectPlus
- #2 - Grammarly
- #3 - Ithenticate
- #4 - Unicheck
- #5 - Scribbr
- #6 - Quetext
- #7 - Duplichecker
- #8 - Copyscape
- Which plagiarism checker really comes out on top?
8 Top Plagiarism Checkers Compared Side-by-Side (2025)
| Tool Name | Pros | Cons | Pricing |
|---|---|---|---|
| AIDetectPlus |
|
|
$9/5k, $14/20k, $24/40k credits; $19/mo unlimited. |
| Grammarly |
|
|
Free basics; Premium unlocks advanced features |
| iThenticate |
|
|
$125/1 paper, $300/3; expires in 1 year |
| Unicheck |
|
|
Only for schools, no public pricing |
| Scribbr |
|
|
No free trial; $20+ each use |
| Quetext |
|
|
Free plan limited; upgrades affordable |
| DupliChecker |
|
|
Free with 1,000-word limit, pay to upgrade |
| Copyscape |
|
|
Free basic; premium needs credits |
#1 - AIDetectPlus
What does AIDetectPlus Do?
Hey, if you ever need to check your writing for plagiarism or AI content, AIDetectPlus does it all in one dashboard. It spots AI-generated stuff, flags plagiarism, and even tweaks your writing so it sounds completely human. There’s no confusion here, just easy tools for students, researchers, and honestly, anyone who just wants to write undetectable essays. All that, and you get a solid 1000 word free trial before you even think about paying.
Does it Have a Free Trial?
Yup, you get a 1000 word free trial. There’s zero credit card games—just upload your text and see how well it works. No pressure, no subscriptions hanging over your head.
What Does AIDetectPlus Do Well?
- All-in-one platform: You aren’t stuck with just a plagiarism checker—AIDetectPlus lets you detect AI (claims 97% accuracy!), humanize your essays, and even write undetectable content. Want to paraphrase? Or chat with PDFs? You’re covered. There’s a free LLM chatbot included too!
- They give you a generous free trial—and when you upgrade, you just buy credits that never expire. None of those annoying monthly fees, just straight-up one-time payments.
- It’s built for real people—there are tools for students, marketers, and teachers. You pick what works for you.
- The humanizer spits out text with no grammar mistakes and there’s no input size limit, so you don’t need to chop up your essay or worry about losing formatting.
- Support is actually responsive. If you hit a snag, you’ll get real help—fast. No waiting days for an email reply.
Here's what Natsha (current AIDetectPlus user) said in her review:
“Really appreciated the straight forward pricing with no surprises! AI Detect Plus is an AWESOME tool to help polish up academic and professional writing.”
Where Does AIDetectPlus Fall Short?
- No Mobile App Yet: You can only use the web version on your phone. It works, but honestly, it’s not as smooth as a dedicated app. Most people probably use their laptop for this kind of thing, but still—it’d be cool to have more options.
- Proprietary Algorithm: You won’t see the exact science behind how it detects AI. That’s standard for this field, but if you like to know every detail under the hood, you might wish for more transparency.
What Does AIDetectPlus Cost?
- $9 (One-Time Payment) - Get 5,000 credits (1 word = 1 credit). Use them for detection, humanizing, plagiarism checks, or even writing help. Not sure if you’ll need more? This plan’s perfect to try everything out.
- $14 (One-Time Payment) - Snag 20k credits, and you can use them whenever. There’s no ticking clock—they never expire.
- $24 (One-Time Payment) - You’ll get 40k credits—way more for your bucks (and saves you a solid 40%).
- Unlimited Plan - $19/month gets you unlimited words. Use it nonstop, cancel anytime—no stress at all.
#2 - Grammarly
What does Grammarly Do?
So, Grammarly is basically your online writing sidekick. It checks your spelling, grammar, punctuation, and even your tone while you type. Whether you’re writing emails, essays, or a killer blog post, Grammarly just quietly points out where you’re messing up and gives you better ways to say things. It’ll also highlight wordiness and those weird sentences you accidentally crank out.
Does it Have a Free Trial?
Yep, you can get started with Grammarly for free, and honestly, the free trial covers a lot—basic grammar, spelling, and punctuation checks. But once you try Premium, it’s tough to go back! That’s where all the advanced features and detailed feedback live.
What Does Grammarly Do Well?
- Super Simple to Use: It works everywhere—browser extensions, Word, Google Docs—and the interface just makes sense.
- Custom Feedback: The suggestions actually adapt to your writing style and you can set goals like tone, formality, and audience. It’s kind of spooky how well it gets you.
- Crazy Good Plagiarism Checker: Premium checks your stuff against billions of web pages so you never accidentally copy someone else’s work.
Where Does Grammarly Fall Short?
- Gets Slow with Big Docs: If your document is over 3,000 words, the editor lags hard and sometimes just freezes.
- So-So for Academic Stuff: It’s just not built for hardcore research or technical papers—misses jargon and messes with stats formatting.
- Annoying Reminders: The free version is always bugging you to upgrade, which gets old real quick.
- No PDF or Markdown Support: You can forget about working straight from PDF or technical files—it just doesn’t work.
- Not Always Right: Sometimes the suggestions are off or just plain wrong—don’t blindly accept everything it tells you!
If you want to know more about Grammarly, you can read the in-depth Grammarly Review blog I wrote recently.
#3 - iThenticate
What does iThenticate Do?
If you’re serious about academic writing or publishing, iThenticate is the plagiarism checker you’ll probably hear about first. It checks your work against a gigantic database of research papers, journals, and books, so it’s made for catching copied text that other tools totally miss.
Does it Have a Free Trial?
Nope, iThenticate doesn't let you try before you buy. If you want to see how it works, you’ve got to pay upfront—no free samples or sneak peeks at all.
What Does iThenticate Do Well?
- Massive Database: It checks your writing against millions of published resources, so you’ll catch stuff you didn’t even know was there.
- Super Simple Interface: Even if you’re not a tech whiz, the dashboard makes uploading and checking a breeze.
- Really Detailed Reports: It shows you exactly what parts of your document match other sources, so fixing issues is way easier.
Where Does iThenticate Fall Short?
- Customer Support is Painful: Waiting for help takes forever and refunds are a nightmare to get sorted.
- Unused Credits Disappear: If you don’t use all your credits before they expire, they’re gone. No rollovers, just lost money.
- Super Pricey: Seriously, the cost is way higher than most other plagiarism tools out there—even when they do a similar job.
- Limited File Types: If your document isn’t in the right format, you’re stuck converting it just to run a check.
- No Free Trial: You’ve got to pay right out the gate, which is risky if you just want to test things out first.
What Does iThenticate Cost?
- Single Plan: $125 for one manuscript (up to 25,000 words). Five free revisions, but credits are gone if not used in 12 months.
- Multiple Plan: $300 for three manuscripts or one big paper. Still five revisions each, credits expire after a year.
- Organization Plan: Custom pricing—gotta talk to sales, and it’s usually expensive. No public pricing, so expect a big quote!
- No AI Detection: None of the individual plans check for AI writing at all.
#4 - Unicheck
What does Unicheck Do?
If you’re a teacher or a student, Unicheck scans your assignments for plagiarism right inside your school’s LMS, like Canvas or Google Classroom. It checks your work against the internet, its own library, and even past student papers. Plus, reports come loaded with color codes—so it’s super easy to spot what you need to fix.
Does it Have a Free Trial?
Unicheck doesn’t let you make new accounts anymore, but if your school already uses it, you can ask for a 60-day demo to try all the features out for free—just gotta go through your education institution.
What Does Unicheck Do Well?
- Super smooth LMS integration: Works perfectly with Canvas, Moodle, Google Classroom, and more—everything’s automatic.
- Easy-to-read reports: The color coding and instant feedback make it simple for anyone to know what parts to edit.
- Smart plagiarism detection: Catches even sneaky paraphrasing, so you can trust the originality check.
Where Does Unicheck Fall Short?
- No more individual accounts: If you’re not in K-12 or higher ed, you’re out of luck—no signups allowed anymore.
- Pricey compared to rivals: It’s more expensive than other academic plagiarism checkers out there.
- No real-time editing: You can’t fix stuff on the fly—you need to download reports and edit elsewhere.
- Limited citation formats: Only works great with APA, MLA, Turabian, Harvard, or Chicago—bad news for bloggers.
- Steep learning curve: Even with guides, it can take a while to figure out all the features.
What Does Unicheck Cost?
- No more public pricing: New sign-ups and individual/business plans are gone—only schools can use it now.
- Free 60-day trial: Educators can request a demo for up to two months, but after that, it’s institution-level pricing (and not cheap).
#5 - Scribbr
What does Scribbr Do?
Scribbr is all about helping you nail academic writing. It offers editing, proofreading, and a plagiarism checker powered by Turnitin. Plus, it can generate and organize citations for your essays and research papers.
Does it Have a Free Trial?
Nope, Scribbr doesn’t give out free trials. Every time you want to check for plagiarism or get your doc edited, you gotta pay upfront—no freebies, no monthly plans, just pay-per-use.
What Does Scribbr Do Well?
- Killer Editing Feedback: Real human editors give super detailed advice to make your paper clearer and way easier to read.
- Top-Notch Plagiarism Checks: Since it’s powered by Turnitin, you get really accurate plagiarism reports that most professors trust.
- Handy Citation Tools: Managing references gets way less stressful, especially if your brain is fried from juggling a bunch of classes.
Where Does Scribbr Fall Short?
- Way Too Pricey: Want to check just one paper? That’ll cost you $20 or more—every single time. If you need to scan lots of docs, your wallet’s in trouble fast.
- No Refunds, Period: If Scribbr screws up or you buy by mistake, don’t expect your cash back—they’re strict about no refunds.
- Sketchy Customer Support: When you actually need help (especially if you’re on a deadline), it can feel like yelling into the void.
- Fake Plagiarism Warnings: The free checker flashes scary high plagiarism scores to push you into paying, but after you pay, it turns out to be harmless stuff like your references.
- Your Data Isn’t Private: Once you upload your work, Scribbr keeps it—and it’s super unclear how long or what they do with it.
If you want to know more about Scribbr, you can read the in-depth Scribbr Review blog I wrote recently.
#6 - Quetext
What does Quetext Do?
If you wanna catch plagiarism fast, Quetext’s your go-to. Just drop your text in, hit scan, and it spits out a color-coded report showing everything that looks suspicious and where it came from.
Does it Have a Free Trial?
Yeah, but honestly, the free plan is tiny—one short page and you’re done. After that, they push you hard to upgrade if you want to check more than a measly paragraph.
What Does Quetext Do Well?
- Super Easy to Use: Just copy, paste, and go—no messing with tricky menus or settings at all.
- Detailed Reports: The results are clear as day, with colored highlights and super simple side-by-side source matching.
- Decent Pricing: If you do upgrade, it’s actually pretty affordable for students and teachers compared to some other checkers.
Where Does Quetext Fall Short?
- Awful Free Plan: You barely get to try it before it blocks you and asks for cash.
- Lost Credits: If you don’t use all your monthly credits, they just vanish—no rollovers, which sucks.
- Customer Service is Slow: If you run into a problem, good luck—support takes forever to get back, if they even reply.
- Flags References by Mistake: Even your properly cited sources can get marked as plagiarism, which is super frustrating.
- Results Aren’t Always Accurate: Sometimes it misses real plagiarism or gives you a fake clean report that isn’t safe for school or work.
If you want to know more about Quetext, you can read the in-depth Quetext Review blog I wrote recently.
#7 - DupliChecker
What does DupliChecker Do?
DupliChecker is a free online tool where you can quickly check your text for plagiarism, grammar errors, or even count words—no account needed, just paste your text or upload a doc and hit the button. It’s super beginner-friendly and you get instant feedback in seconds, which is perfect if you want to do a super fast check before hitting publish!
Does it Have a Free Trial?
Yep, you can use DupliChecker for free, but you’re capped at 1,000 words per scan—so if your document’s long, you’ll be chopping it into pieces. No account or hoops to jump through, just use it right away, but for serious or heavy use, you’ll quickly run into the limits and have to pay for more.
What Does DupliChecker Do Well?
- No Sign-up Hassle: You can just jump in and check your text—no sign-up forms or waiting around.
- Multilingual & Grammar Checks: It checks for plagiarism and grammar in several languages, which is super handy if you’re not always writing in English.
- Downloadable Reports: You get to download neat reports for sharing or saving your plagiarism results, so no more annoying screenshots!
Where Does DupliChecker Fall Short?
- Misses Paraphrased & Hidden Plagiarism: It pretty much only catches word-for-word copying, and often misses stuff that’s been reworded or hidden behind paywalls.
- Super Ad-Heavy: The site is filled with ads that are honestly just a pain—you’ll be dodging pop-ups while trying to check your work.
- 1,000-Word Limit Per Scan: You’re stuck checking big documents in short chunks, which gets annoying fast.
- Privacy Isn’t Clear: They say they don’t keep your documents, but there isn’t a solid privacy policy, so don’t trust it with your secret or sensitive stuff.
- Bad Customer Support & Refunds: If you sign up and need help or a refund, you might be waiting forever—and don’t expect to get your money back easily.
If you want to know more about DupliChecker, you can read the in-depth DupliChecker Review blog I wrote recently.
#8 - Copyscape
What does Copyscape Do?
If you want to know if your site’s content is floating around elsewhere, Copyscape’s got your back. Just slap in a URL or paste your text, and boom—it checks the web for any copycats. Whether you run a blog, an agency, or just want to keep your stuff original, this tool makes sure your content isn’t being ripped off somewhere else.
Does it Have a Free Trial?
Yep, there's a free version so you can do some basic checks without paying a cent. But if you want all the bells and whistles, like bulk searching and private content checks, you’ll wanna try Copyscape Premium.
What Does Copyscape Do Well?
- Super simple interface: You don’t need a manual—just jump in and start scanning.
- Trusted by the pros: This tool’s been around forever and loads of publishers swear by it.
- Handy URL scanning: Pop in any web link and instantly see if it’s been copied elsewhere.
Where Does Copyscape Fall Short?
- Weak with paraphrased stuff: It’s awesome for direct copies, but if someone rewrites your content, it probably won’t catch it.
- Not great with AI rewrites: AI-generated copy can slip right through if it’s not an exact match.
- Doesn’t scan academic sources: It sticks to the open web, so forget about finding copied journal articles or citations.
- Credit system can get pricey: If you’re scanning loads of content, those credits can add up fast.
- Unused credits expire: Don’t let your credits go to waste—they disappear if you don’t use them in time.
Which Is The Best Plagiarism Checker For Students And Researchers?
Quick answer – A bunch of them just aren't worth your time.
Let me tell you why most of these other tools just don’t cut it:
- Reason #1: Terrible Customer Service: Whenever I tried reaching out to these guys, it felt like I was talking to a wall. Slow replies, unhelpful answers, and if you ever need a refund or want to cancel—good luck getting a response. Totally frustrating, trust me.
- Reason #2: Overcharging For Credits: Here's the worst part—whatever credits you don’t use just vanish at the end of the month. Even on those so-called "annual" plans. You pay, but you never get what you paid for.
- Reason #3: Inaccurate Reports & Missed Sources: Some tools miss giant chunks of copied content or flag stuff that’s clearly original. From my own experience, they catch the obvious stuff but totally skip the tricky bits. In the end, you’re not really protected.
So what do you do instead?
Honestly, AIDetectPlus fixes all these headaches. Let me show you how:
First off, you can actually try it for free—up to 1000 words, no tricks. But here’s what really makes it different:
- #1 Accurate, Real-Time Plagiarism Checks: It checks billions of sources super fast, highlights the actual pieces copied, and shows you where they came from. When I used it for my own essays, it found stuff other checkers completely missed and helped me fix it right away.
- #2 Credits NEVER EXPIRE, Ever: Your credits stick around until you use them. Buy them once, and you’re set. No more “use it or lose it” nonsense.
- #3 Friendly, Real Customer Support: When I had a question, a real person replied super quick—usually within the same day, sometimes even in an hour. No chatbots, no waiting forever, just help when you need it.
- #4 Everything In One Spot: Besides plagiarism checks, AIDetectPlus also gives you AI detection, text humanizing, paraphrasing, Chat with PDF, and even free LLM chat. Whether you’re a student, teacher, or blogger, it’s all made for you. Check out everything via the menu above.
That’s it! I hope this helped you dodge the bad choices and find a plagiarism checker you’ll actually love. If you want to see how AIDetectPlus works, just visit our website or start your 1000-word free trial. No credit card or phone number needed—only your email, and you’re good to go!