The Best Proofreading Software in 2026: A PerfectIt Walkthrough
PerfectIt is the best proofreading software for professional consistency and house style checking in Microsoft Word. It’s not AI, and it doesn't generate or rewrite text. Rather, PerfectIt helps you to apply your rules the same way every time. It points out consistency issues and lets you check a document against your house style.
PerfectIt flags inconsistencies like mixed regional spelling, an undefined acronym, and inconsistent capitalization, and then hands the decision to the user.
That focus is why medical writers, proposal teams, legal departments, and government publication teams rely on PerfectIt. PerfectIt helps them produce multi-author documents on tight deadlines that read as if they are written in one voice.
PerfectIt is the only official proofreading software of The Chicago Manual of Style, through a formal partnership that builds CMOS’s rules directly into the checks. It's also the only official proofreading software of the Microsoft Writing Style Guide.
This walkthrough puts PerfectIt to work on a real example: a technical proposal with a handful of multi-author slip-ups planted on purpose.
How to set up PerfectIt in Word on Windows and Mac;
What a check catches: mixed spelling, shifting capitalization, inconsistent hyphenation, and an acronym used before it's defined;
How the sidebar walks through one inconsistency at a time, so that final decisions are always made by the user;
And a look at the built-in styles and customization capabilities, along with PerfectIt's limitations.
What PerfectIt Actually Is
PerfectIt is a consistency and house style checker for Microsoft Word and PowerPoint. It helps with the repetitive, mechanical checking, like abbreviations, terminology, and capitalization, freeing up time writers and editors could otherwise spend on meaning and communication.
Unlike a spellchecker, which checks words in isolation against a dictionary list, PerfectIt reads your whole document at once and flags how terms shift across tens or hundreds of pages. It catches things like 'Project Lead' on page 1 turning into 'project lead' by page 21, or 'double-blind' turning into 'double blind' partway through the same document.
The result is a document written in one voice, without inconsistencies the user has to catch by rereading the whole thing.
PerfectIt covers these distinct consistency checks:
Acronym definitions: Flags acronyms used before they're defined, defined twice, or never defined at all.
Table of acronyms: Creates a table of every acronym in the document.
Capitalization: Catches terms with initial capitals in one location and lowercase in another.
Hyphenation: Flags words hyphenated in one place but not another.
Bullet and list punctuation: Ensures consistent punctuation in bullets and numbered lists.
Spelling: Flags mixed US and UK spellings in the same document.
Numbers in sentences: Points out a number written as a word in one location, like "six," and as a digit in another, like "7," within the same document.
Tables and figures: Checks that they're titled consistently and appear in numerical order.
House style sits above these checks as its own layer. It applies an organization's own editorial rules across all of them. Once built, it’s easy to enforce on every document that follows.
Acronym Checking
Acronym checking is one of the most important reasons why professional teams use PerfectIt in the first place. An acronym used before it's defined, defined twice in different sections, or never defined at all might be easy to miss on a first read. PerfectIt catches all three, with over 90 percent accuracy, without touching any AI.
An undefined acronym in a proposal can confuse an evaluator, even when the rest of a proposal is strong. The same mistake in a regulatory submission can lead to questions that slow down approval. Government publications teams run into a version of this too, since a document with several authors often ends up defining the same term twice, or not at all.
PerfectIt handles that checking so nobody has to track every acronym by hand across a long document. It also builds a table of every acronym used in the document, ready to drop into a proposal's front matter or a report's appendix.
Getting Started: Installing and Setting Up PerfectIt
PerfectIt runs as a Microsoft Word add-in. Run the PerfectIt installer on Windows, where it works fully offline once installed, or get it from the Microsoft Marketplace on Mac. Check PerfectIt's website for full setup details.
PerfectIt for PowerPoint
PerfectIt for PowerPoint runs on Windows and is in the Elite, Team, and Enterprise plans.
Free Trial
PerfectIt offers a 14-day free trial with full access, so you can follow along with the rest of this guide on your own device. You don’t need to buy anything or give any personal information other than your email address.
Step-by-Step Walkthrough: Running PerfectIt on a Real Document
This walkthrough uses an excerpt from a technical proposal. It’s written the way most proposals are written: several contributors, several passes. The excerpt includes a few inconsistencies planted on purpose, each matching a different PerfectIt check:
Hyphenation: "email" appears once, then "e-mail" shows up a couple of paragraphs later.
Capitalization: "Steering Committee" is capitalized the first time it's mentioned, then written as "steering committee" later in the same section.
Spelling variations: "center" and "centre" both appear, mixing US and UK spelling in the same document.
Abbreviation used before its definition: "SLA" is used in a sentence before "Service Level Agreement (SLA)" is ever defined.
Step 1: Open PerfectIt in Word
To start PerfectIt, click the PerfectIt tab in the ribbon, then click Launch PerfectIt. The sidebar opens next to the document.
Step 2: Choose a Style
PerfectIt will ask you which style to check against before starting. Since the proposal is for a US-based client, we could select US spelling as the base style from the Current Style dropdown.
A team with its own house style would customize and apply that instead, enforcing the same terminology no matter who wrote each section. In this case, we’ll just use PerfectIt’s default option “Check Consistency” for the rest of this walkthrough.
Step 3: Start the Check
After PerfectIt launches, a progress window appears while it reads through the document. It also shows a reminder to review every suggestion as PerfectIt doesn't fix anything on its own.
Step 4: Review Each Issue
Once the check finishes, the sidebar fills in one category at a time. Hyphenation shows up, comparing "email" against "e-mail," with the flagged location highlighted in the document. From here, there are three options: accept the fix, edit it by hand, or leave that instance as is. The decision is up to the user.
The capitalization category flags "steering committee" against "Steering Committee” while the Spelling Variations category catches "center" against "centre."
Abbreviations Used Before Definition flags "SLA" before "Service Level Agreement (SLA)" is spelled out.
Every document is different, so the issues that show up will depend on what's actually in your document.
Step 5: Final Polish
PerfectIt offers a set of finalization tasks to finish it all off. Just select a task and click ‘Go’.
When to Run PerfectIt
There's no single right moment to run a check. Some teams run it right after the first draft, before editing starts in order to save time on the edit. Others wait until after the first editing pass so that PerfectIt is only used on the (almost) final text.
Some run it at both points: early and again at the end, since new inconsistencies can creep in during editing itself. Whichever point you pick, PerfectIt will catch the kind of inconsistency that's easy to miss across fifty pages but that jump out at readers. It's a check, not a stand-in for drafting or editing.
Context and Exceptions
Not every flag PerfectIt shows needs a fix. It shows every instance of an inconsistency so a person can make difficult editorial decisions and decide what's actually wrong based on the context.
Two exceptions come up often. A quoted line usually stays exactly as written, even if it clashes with the rest of the document. The same goes for terms in titles or names.
That's the advantage of checking every location individually. PerfectIt flags each one, but the user still decides what actually needs to change.
PerfectIt’s Built-in Styles and Your House Style
PerfectIt's consistency checking doesn't require any customization. Every inconsistency in the walkthrough above was found straight out of the box, no customization required.
The built-in styles take this concept further. On the spelling side, there are US, UK, Canadian, and Australian. Beyond that, PerfectIt includes a set of organizational styles: American Legal Style, Australian Government Style, European Union Style, GPO (US Government Publishing Office) Style, United Nations Style, Microsoft Style, and WHO Style.
The Chicago Manual of Style sits in a category of its own here. PerfectIt is the only official proofreading software of The Chicago Manual of Style, and holds that same official status with the Microsoft Writing Style Guide. Checking against CMOS requires a separate CMOS Online subscription.
The next level up is customization.
Most teams already have a house style of their own, and PerfectIt makes it easier to enforce, catching things a built-in style can't, because they're specific to the company: a specialized terminology unique to one industry, the company’s correct spelling and capitalization, or a phrase the legal department insists on every time.
All of that gets built once in Styleworks (styleworks.app), the separate tool for building a house style for PerfectIt. That house style then works across any version of PerfectIt, checking every document from then on, not just the one open at the time.
Some teams try using an AI tool to check a document against a style instead. But AI approximates a style guide's rules rather than enforcing them, and that gets shakier the longer a document runs or the more specific the rule. PerfectIt's official partnerships mean the real, published rules are built in directly, not just approximated.
Pricing and Plans
PerfectIt is sold as an annual, per-user license, with four tiers to choose from.
Professional: (1-3 users): consistency and acronym checks, house style and preference checks, sharing house styles across a team, CMOS checking with an active subscription, offline working, and standard support and billing.
Elite: (1-3 users): everything in Professional, plus PowerPoint checking, which runs on Windows.
Team: (3-100 users): everything in Elite, plus live, expert-led training and personalized procurement support.
Enterprise: (1+ users): everything in Team, plus a dedicated account manager, personalized installation and deployment support, priority support, and live training tailored to your team.
PerfectIt offers a 14-day free trial with full access and no credit card required.
Who PerfectIt Is For
PerfectIt started as software for professional editors and has grown to more than 20,000 users across 72 countries. It's built for teams and organizations sending out documents that represent them, often with several people involved in the writing. In particular, in addition to professional editors, it’s used by proposal writers, medical writers, and government publications teams.
Proposal writers
A single inconsistent term can cost an organization's reputation and credibility. This is why many proposal teams depend on PerfectIt. Microsoft's global proposal team credits it with cutting time spent on document mechanics, leaving more time for strategic edits. BidExecs, a proposal management company, reports a 30 percent cut in proofreading time using PerfectIt.
Medical writers
Medical writing teams rely on PerfectIt, especially in regulatory medical writing. "Participant" and "subject" aren't interchangeable in a clinical trial report. Someone who agreed to take part is a "participant," not a "subject." But subject-matter experts often get this the wrong way around. And mistakes mixed across a hundred-page document with multiple writers, can make the wrong impression.
PerfectIt finds those errors. That’s why 80 percent of the world's largest pharmaceutical companies use it across their entire medical writing team, as well as Cancer Research UK's Centre for Drug Development.
Other teams
Government publications teams, legal, consulting, and academic publishing all need the same thing: consistency and a document that reads as if it’s one voice by the time a document goes out.
Grammar, typos, and sentence clarity sit outside of PerfectIt's remit. Those are for the user to handle. PerfectIt is for longer documents, not a two-line email.
How PerfectIt Differs From AI Writing Tools
PerfectIt applies the same rules every time, instead of generating text, rewriting sentences, or deciding what a paragraph should say. That puts it in a different category from AI writing tools, even though people searching for the best proofreading software often land on both.
AI tools like Grammarly or editGPT work differently. They draft and rewrite text. That's a different job from checking a document for consistency and house style. PerfectIt doesn't compete with these tools. But it actually works well after using one.
Some teams today draft with AI first. Then they need something to catch the terminology drift that creeps in once a document has a few AI-assisted passes on it. PerfectIt is built for that step, not the drafting step.
That distinction matters most for teams that hesitate to send confidential documents to AI tools at all. PerfectIt runs fully offline on Windows, so nothing gets sent to an outside model or used for training.
For a pharmaceutical company or a government agency, that makes internal approval a lot easier to get.
Frequently Asked Questions
Is PerfectIt an AI tool?
No, PerfectIt applies your rules the same way every time, checking a document against a style rather than generating anything new. It flags what doesn't match and leaves the writing itself untouched. No document data goes to an AI company or gets used to train anything.
What does PerfectIt check?
PerfectIt checks consistency issues and house style such as abbreviations and acronyms, capitalization, hyphenation, bullet and list punctuation, regional spelling, numbering, and table or figure numbering. House style is the layer sitting over these, letting a team apply its own specific rules on top of the built-in checks.
Does PerfectIt work on a Mac?
Yes. PerfectIt works on Mac through Microsoft 365 to check Word documents, but it doesn't work in PowerPoint on Macs.
How much does PerfectIt cost?
PerfectIt is sold as an annual, per-user license across four tiers (Professional, Elite, Team, and Enterprise) with a free trial available before buying. Plans do get updated, so make sure to confirm directly at PerfectIt’s site.
Can PerfectIt replace a human proofreader or editor?
No. It speeds up the part of the workflow that used to mean scrolling back and forth checking every instance of a term by hand. PerfectIt doesn't make editorial decisions. It brings difficult editorial decisions to the attention of the user and it makes it easier for the user to make changes.
Is PerfectIt legitimate, and who makes it?
PerfectIt is made by Intelligent Editing. Medical writing teams at 80 percent of the world's largest pharmaceutical companies use it, as does Microsoft's global proposal team. It holds 4.9 out of 5 on Capterra and 4.8 out of 5 on G2. It’s also among the highest-rated proofreading tools on the Microsoft Marketplace.
