Spellbook vs StrongSuit (formerly Callidus): contracts or litigation

Spellbook vs StrongSuit at a glance

The table lines the two up on the points that separate a contract tool from a litigation tool and adds Gavel Exec in the right-hand column for reference.

What Spellbook is

Spellbook markets "the complete contract AI suite" to law firms and in-house teams, and its site says the product is built for transactional work on both sides of a deal. The core product is a Microsoft Word add-in with five parts: Review, Draft, Ask, Benchmarks and Playbooks. Review's edits land in the document as native Word tracked changes, with no export step.

Outside Word, Spellbook works in Google Docs, and Associate, an agent that runs in the browser, handles research, review and redlining across document sets such as data rooms and disclosure schedules. When you point Ask at legal sources, it grounds answers in public databases such as CourtListener, CanLII and Justia and cites each source. Spellbook also connects to iManage, SharePoint, OneDrive, Google Drive and Dropbox.

• Price: Spellbook lists no figures. Pricing scales with the headcount on a license, and a demo request gets you a personalized quote. The figure we use is about $350 per user per month, reported by Gavel customers, and it may differ for your team size.
• Trial: Spellbook gives lawyers and legal teams 7 days free and says larger organizations may get an extended trial. Per its help center, a trial started on the website lapses with no charge, while one set up through sales may roll into a paid subscription. In-house teams see "Book a Demo" on the pricing page.
• Market data: Compare sets your terms beside contract data that Spellbook draws from 80+ countries, narrowed by industry, jurisdiction and deal type.
• Security: SOC 2 Type II, plus stated compliance with United States health privacy rules, European Union data protection law and the European Union AI Act. Spellbook negotiated zero data retention terms with both OpenAI and Anthropic and its cloud providers store customer data in Canada and the United States.
• Customers and funding: the homepage counts 5,000+ legal teams, and Spellbook reports raising more than $80 million in equity.

Limits: there's no public price, and Spellbook's own site puts case-law and litigation research outside what it is "primarily designed for." Ask can cite public case law while you work in Word, but a litigation team that needs good-law checks and motion drafting would still want a dedicated research platform.

What StrongSuit is

StrongSuit was called Callidus Legal AI until it renamed itself on November 12, 2025, the date of both StrongSuit's press release announcing the new name and LawNext's report on it. LawNext described the change as the company's evolution "from a legal AI tool into what it describes as an end-to-end litigation platform," and the old callidusai.com address now redirects to strongsuit.com. StrongSuit's About page says the company is "Built for Litigators by Litigators," and its "Built For" menu names solo attorneys, small to large law firms, plaintiff firms, litigation teams and in-house legal teams.

Research sits at the center. StrongSuit's case search covers more than 10 million precedential federal and state cases, adds "good law" analysis and AI summaries of each opinion, and feeds a drafting workflow that turns case facts and research into first drafts of briefs and motions. The platform also builds timelines from the matter record, supports deposition preparation and runs an oral argument simulator with a Case Coach. Contract tools sit alongside these: the Word add-in drafts and redlines agreements, and Compare Contracts checks a counterparty's draft against your reference agreement and can suggest fallback language.

• Price: one attorney on the Individual plan pays $249 a month, and the plan lists access to the platform, the case database and the Word add-in. Firms needing several licenses get a custom quote for the Firm plan, which adds "Access to all StrongSuit features," onboarding run by StrongSuit attorneys, admin controls over who has access, shared work across the team and a "Scaled Doc Review Solution." StrongSuit says "Module access and usage depend on your plan."
• Trial: StrongSuit's help center describes a free trial of 5 days. You confirm the account with a credit card, and section 4.3 of the terms of service charges that card the full subscription fee at the end of the trial unless you cancel first.
• Word add-in: a Litigate tab finds cases, builds a table of authorities and checks that citations name the correct reporter. For contracts, Negotiate reviews an agreement against your instructions or an uploaded playbook, shows each suggestion with its "corresponding track changes," and labels each one High, Medium or Low severity.
• Security: SOC 2 Type II. StrongSuit runs on its own private tenant in Microsoft Azure, keeps stored data inside the United States, and says it never uses customer data to train a model.
• Customers and funding: 1,000+ legal organizations, per its homepage. Legal IT Insider reported in July 2025 that the company raised $10 million in a round led by Cervin Ventures, with Foley & Lardner among the investors.

Limits: StrongSuit's contract pages describe comparison against your own reference agreement or playbook and name no market benchmark data. Clio import and team collaboration come only with the Firm plan, and the pricing page says not all features are available on all plans; beyond the case database and the Word add-in, it doesn't list which modules the Individual plan includes. StrongSuit's pricing page lists a "Scaled Doc Review Solution" under the Firm plan, while its platform page labels the AI Discovery and Document Review module "Enterprise" and offers beta access on a limited number of documents on request. The trial bills your card unless you cancel in time.

Spellbook vs StrongSuit: the differences that matter

Litigation or transactional practice

For most buyers this settles it. StrongSuit is organized around litigation: case research, briefs and motions, timelines, depositions and oral argument practice. Spellbook is organized around contracts and says litigation research isn't its primary workflow. A litigator will use more of StrongSuit, and a deal lawyer will use more of Spellbook.

Case-law research

StrongSuit is stronger on research. It searches more than 10 million precedential federal and state cases, checks whether each remains good law and summarizes holdings, and inside Word it can find support for a highlighted passage, look up a cited case and build a table of authorities. Spellbook's Ask can ground an answer in CourtListener, Case.law or CanLII with citations, which helps with a quick legal question while you work on an agreement, though Spellbook doesn't position it as a research platform.

Contract redlining in Word

Spellbook goes deeper on contracts. Review applies redlines as native tracked changes, Playbooks encode a team's standards, fallback positions and risk thresholds, and Associate runs review and redlining across whole document sets. StrongSuit's Negotiate tool reviews an agreement against an uploaded playbook, labels its suggestions by severity and lets you add comments, and Compare Contracts suggests fallback language against your reference terms. A lawyer who negotiates every day gets more from Spellbook; a litigator who reviews an occasional agreement may find StrongSuit's tools enough.

Market terms

Spellbook is stronger when you need to know what's market. Its Compare feature runs in Word and sets clauses against deal data from 80+ countries and hundreds of industries, so you can see where a term sits for a given industry, jurisdiction or deal type. StrongSuit's contract pages measure a draft against your firm's reference agreement or playbook, which shows where it departs from your own terms. Those pages describe no market dataset.

Pricing and trials

StrongSuit is easier to price. Its Individual plan, at $249 a month per attorney, lists the case database and the Word add-in, and the quoted Firm plan adds access to all StrongSuit features. Spellbook doesn't publish a price. For comparison, this page uses about $350 per user per month for Spellbook, reported by Gavel customers, and Spellbook's pricing depends on how many team members are on the license. Spellbook's trial carries less billing risk: it lasts 7 days, and trials started on its website end without a charge, while StrongSuit holds a card for its 5 days and charges the full subscription fee when they run out unless you cancel.

Where your files and requests live

The integrations point to different practices. Spellbook connects to iManage, SharePoint, OneDrive, Google Drive and Dropbox and works in Google Docs, which suits firms that keep deal documents in a document management system. StrongSuit syncs a Microsoft Outlook folder into a matter and drafts replies from the matter's documents and emails, and its Firm plan imports matters from Clio, which suits litigation practices that run on Clio and Outlook. StrongSuit's Outlook sync works with Microsoft accounts only.

Which should you choose?

• Choose Spellbook if your week is spent on commercial agreements, you rely on market benchmarks and multi-document review in Associate, or your documents live in iManage or Google Docs. A 7-day trial started on Spellbook's website ends without a charge, which makes it easy to test first.
• Choose StrongSuit if your practice is litigation and you need case-law research with good-law analysis, first drafts of briefs and motions, timelines and deposition preparation in one platform, with contract drafting and review available when a matter calls for it. Its Individual plan is posted at $249 a month per attorney, and StrongSuit says module access varies by plan, so confirm which modules yours includes.
• Consider Gavel Exec if contract review is the bulk of the job and you'd like to start without a sales call or a card (25 free queries per user), pay a posted $160 per user per month, build playbooks out of checklists and agreements you've already signed, and see benchmarks narrowed by company size.

A third option: Gavel Exec

Gavel Exec is AI contract review and drafting software that runs inside Microsoft Word as an add-in and on the web. Set against this pair, it sits on Spellbook's side: it is a contract tool with no case-law database, so it fits transactional lawyers and in-house teams better than litigators. In Word it marks up the full agreement, orders its tracked changes by priority, explains why it made each one, and flags terms the draft leaves out.

• Playbooks: start from attorney-drafted playbooks or build rules out of your checklists, spreadsheet playbooks and signed agreements, then share them across the team with read-only or edit rights.
• Benchmarking: in the web app, each provision is labeled on-market, off-market or missing, and you can narrow the comparison by jurisdiction, industry or company size.
• Security: Gavel holds SOC 2 Type II, has Zero Data Retention agreements with its AI model providers (OpenAI among them), and keeps customer prompts, documents and data out of model training. Default hosting is in the United States, and customers can opt for hosting in Canada, Australia or the European Union.
• Price: $160 per user per month, or $1,740 per user per year, with 25 free queries per user and no credit card. Teams of 10 or more seats can get discounted pricing. The monthly plan is billed month to month, with no long-term contract.

Martin Algie says first-cut review at MIA Contract Lawyers now takes about 5 hours per contract with Gavel Exec, against roughly 15 before.

Limits: there is no case-law database in Gavel Exec, and it doesn't handle litigation or electronic discovery work, so for a litigator it can't stand in for StrongSuit. It also has no obligation or renewal tracking for a portfolio of signed contracts, and integrations with iManage or NetDocuments haven't launched. Spellbook vs Gavel Exec walks through that matchup point by point, Gavel Exec for transactional attorneys shows deal workflows, and the Spellbook alternatives roundup lists more contract tools.

How to test Spellbook and StrongSuit side by side

1. Sort last month's work into contracts and litigation. If most hours went to agreements, start with Spellbook; if most went to research, motions and case preparation, start with StrongSuit. The split tells you which product's strengths you would use every day.
2. Schedule the trials so they overlap. Because StrongSuit charges the card you give it once its 5 days are up, note the end date at signup and decide before then. Spellbook's pricing page sends in-house teams to a demo, so request that a few days ahead if you need both windows open at once.
3. Give both the same agreement and the same playbook. Run a recent services agreement through Spellbook's Review and StrongSuit's Negotiate, then check whether each edit arrives as a tracked change your counterparty can accept or reject in Word.
4. Give both the same research question. Put a point of law from a current matter to StrongSuit's case search and to Spellbook's Ask with legal sources turned on, then open every case each one cites and confirm it says what the tool claims.

More comparisons: Spellbook alternatives, Irys vs StrongSuit for litigators weighing StrongSuit, Spellbook vs Harvey, a wider look at AI contract review tools ranked for lawyers, and every Gavel comparison page.