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Side-by-side comparison · Writing & Translation

Copyleaks vs GPTZero vs Originality.ai

Everything that matters when choosing between them, in one place: our rating, what each can do, what they cost, and the trade-offs.

Copyleaks

3.9

From $0

Best overall

GPTZero

4.2

From $0

Originality.ai

4.1

From $14.95/mo

Comparing 3 tools, the maximum.

At a glance

Pick it if: Schools, publishers and businesses that need AI and plagiarism checks together, especially across several languages.

Best overallEasiest to use

Pick it if: Teachers, editors and business owners who want a second opinion on whether writing they've been handed came from AI.

Pick it if: Publishers, content agencies, SEO teams and businesses that commission written content and want to check it before publishing.

Overview

AttributeCopyleaksGPTZeroOriginality.ai
In one lineChecks text for AI writing and plagiarism in one scan, in over 30 languages.Checks whether text was written by AI, with plagiarism and citation checks too.Checks content for AI writing, plagiarism and factual errors before you publish it.
Pricing modelFreemiumFreemiumFreemium
Starting price$0$0$14.95/mo
Free plan Yes Yes Yes
Works with Claude Code Yes Yes Yes

Rating breakdown

Our scores out of 5. The higher bar in each row is highlighted.

AttributeCopyleaksGPTZeroOriginality.ai
Overall rating3.94.2Winner4.1
Ease of useHow quickly someone non-technical gets value from it.
4.0
4.5
4.0
FeaturesHow completely it covers its own job, and how well the pieces fit together.
4.5
4.5
4.5
Output qualityHow good the results are before you fix them.
3.5
3.5
3.5
Value for moneyWhat you get for the price, including the free plan.
3.5
4.0
4.0
Speed & reliabilityHow fast it is and how often it falls over.
4.0
4.5
4.5

Feature comparison

A tick means it does this today. A dash means we haven't checked.

AttributeCopyleaksGPTZeroOriginality.ai
Access & platform
Free plan Yes Yes Yes
Mobile app No No–
Desktop app–––
Browser extension Yes Yes Yes
API access Yes Yes Yes
Teams & business
Team workspace Yes Yes Yes
Enterprise plan or SSO Yes Yes Yes
Connects to other apps Yes Yes Yes
Open source or self-hosted Yes No No
AI abilities
Works with your files Yes Yes Yes
Understands images Yes––
Makes images No No No
Makes video No No No
Writes code No No No
Runs agents or automations No No No
Learns your brand or style–––
Works in many languages Yes Yes–
Capabilities score10/ 178/ 177/ 17

Pricing

Plans as listed on each vendor's site when we last checked. Confirm before you buy.

AttributeCopyleaksGPTZeroOriginality.ai
Plans

Free

$0

Quick one-off checks.

Free

$0

Checking the odd document.

Free

Free

Checking the odd article.

PersonalOur pick

$16.99/mo, or $13.99/mo billed yearly

Individuals checking work regularly.

PremiumOur pick

$23.99/mo, or $12.99/mo billed yearly

Teachers and editors checking work every week.

ProOur pick

$14.95/mo, or $12.95/mo billed yearly

Agencies and site owners checking content every week.

Pro

$99.99/mo, or $74.99/mo billed yearly

Teams and agencies.

Professional

$45.99/mo, or $24.99/mo billed yearly

Agencies and heavy users scanning lots of files.

Enterprise

$179/mo, or $136.58/mo billed yearly

Publishers and large content teams.

Enterprise and Education

Custom

Companies and schools at scale.

Team

Professional price per seat, 2 seats minimum

Schools and businesses buying for a group.

Which plan to pickTry the free checker first. Personal covers about 100 pages a month, which suits most individuals. Only move to Pro if a team needs seats or you want website scans. One credit covers 250 words or one image.Start on Free. If you check more than a few documents a week, Premium on yearly billing is the sweet spot. Professional only makes sense if you scan big batches of files.Pro is enough for most agencies and site owners. An AI and plagiarism check together uses two credits per 100 words, so budget about 100,000 words of checked content a month. Go Enterprise only if you need the API or very high volume.

Key features

AttributeCopyleaksGPTZeroOriginality.ai
Standout features
  • AI and plagiarism in one report
  • Many languages
  • AI image detection
  • Website scans
  • Works where you are
  • API and school integrations
  • AI detection
  • Plagiarism check
  • Writing replay
  • Citation and hallucination check
  • Batch scans
  • API and school integrations
  • AI detection
  • Plagiarism checker
  • Fact checker
  • Bulk and site scans
  • Writing replay
  • API

Pros and cons

AttributeCopyleaksGPTZeroOriginality.ai
Pros
  • AI and plagiarism checks in one report
  • Best multilingual coverage of the major detectors
  • Catches plagiarism translated from another language
  • MCP access lets you scan from Claude
  • Checks images as well as text
  • Clear sentence-level highlights, so you see exactly what looks AI-written
  • Generous free plan for occasional checks
  • Writing replay gives honest writers a way to prove their work
  • Flags made-up citations, which most detectors don't
  • API and batch scans for larger volumes
  • AI, plagiarism, facts and readability in one scan
  • Cheap for the volume on Pro
  • Bulk and whole-site scanning
  • Writing replay gives honest writers a way to prove their work
  • API for content teams
Cons
  • Like all detectors, it can flag human writing
  • Personal plan's word allowance is small
  • Big jump in price from Personal to Pro
  • Switching plans wipes unused credits, and refunds are strict
  • Overlaps almost completely with Originality.ai
  • False positives happen, and short or formal writing gets flagged more often
  • Edited or reworded AI text can get past it
  • The best scan and plagiarism checks need a paid plan
  • Mostly designed around schools, so some features won't matter to a business
  • False positives are a recurring complaint, and independent tests find more than the vendor claims
  • Monthly credits expire if you don't use them
  • API is only on the expensive Enterprise plan
  • A score can sour a client or writer relationship if treated as proof

Who each one is for

AttributeCopyleaksGPTZeroOriginality.ai
Best for
  • AI and plagiarism checks in one report
  • Checking content in languages other than English
  • Scanning a whole website for copied pages
  • Checking images for AI
  • Checking essays and assignments for AI writing
  • Screening freelance or agency content
  • Spotting made-up citations in reports
  • Showing you wrote a document yourself
  • Checking freelance and agency content
  • AI and plagiarism checks in one scan
  • Fact-checking articles before they go live
  • Bulk scanning a website
  • Proving a writer wrote their own draft
You'll find it used by
  • Schools and universities
  • Publishers
  • Content agencies
  • Compliance teams
  • Students
  • Teachers
  • Editors
  • Content agencies
  • Recruiters
  • Students
  • Content agencies
  • Publishers
  • SEO teams
  • Marketing managers
  • Website buyers

Questions people ask

Which is better, Copyleaks, GPTZero or Originality.ai?

GPTZero scores highest overall in our ratings (Copyleaks 3.9/5, GPTZero 4.2/5 and Originality.ai 4.1/5). Copyleaks is best for AI and plagiarism checks in one report and checking content in languages other than English. GPTZero is best for checking essays and assignments for AI writing and screening freelance or agency content. Originality.ai is best for checking freelance and agency content and AI and plagiarism checks in one scan.

Which is cheaper, Copyleaks, GPTZero or Originality.ai?

Copyleaks: There's a free plan, and paid plans start at $0. GPTZero: There's a free plan, and paid plans start at $0. Originality.ai: There's a free plan, and paid plans start at $14.95/mo.

Which is easier to use, Copyleaks, GPTZero or Originality.ai?

GPTZero rates highest for ease of use in our scores. Teachers, editors and business owners who want a second opinion on whether writing they've been handed came from AI.

How we compare

Ratings are our own, from using each tool, across ease of use, features, output quality, value for money, speed & reliability.

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