ClauseGuard vs Spellbook: AI Contract Review Comparison

Spellbook lives inside Word. ClauseGuard gives you a complete contract intelligence platform — for a fraction of the cost.

ClauseGuard is an AI-powered contract review platform that analyzes legal agreements for hidden risks, missing clauses, and one-sided terms in 90 seconds. It provides automatic risk scoring, clause-by-clause analysis with market-standard comparisons, and AI-generated redline suggestions in three negotiation tones.

Spellbook: Spellbook is an AI contract drafting and review tool built as a Microsoft Word add-in. It uses OpenAI GPT-4 and is aimed at law firms and legal departments. Pricing requires a demo call with no public pricing.

13
ClauseGuard wins
2
Tied
1
Spellbook wins
Feature
ClauseGuard
Spellbook
Purpose-built for contracts
Yes — full contract intelligence platform
Yes — Word add-in for contract drafting and review
Risk score (0-100)
Automatic weighted risk score per clause and overall
No quantified scoring — flags issues without numeric assessment
3-tone redline generation
Firm, balanced, and collaborative replacement language for every risky clause
Suggests alternative language but in a single tone
Negotiation simulator
Predicts counterparty response per redline with deal probability %
No — no negotiation prediction feature
DOCX export with tracked changes
Download complete Word doc with tracked changes ready to send
Edits happen inline in Word — no separate export needed
Missing clause detection
Automatically identifies absent standard clauses with suggested language
Can suggest missing clauses but not consistently structured
Contract comparison
Side-by-side analysis of 2 contracts, plus multi-compare for 3-10
No built-in contract comparison feature
Obligation tracker + alerts
6 alert types, AI weekly digest, custom reminders, Slack integration
No obligation tracking or deadline alerts
Portfolio dashboard
Risk trends, exposure monitoring, portfolio health score across all contracts
No portfolio-level analytics
Jurisdiction-aware analysis
Select from 16 jurisdictions — redlines cite applicable law
General legal knowledge, not jurisdiction-specific
Custom clause library
Upload your firm's preferred language, engine uses it for redline generation
Has clause suggestions but no user-uploadable library
Developer API
REST API with key management for programmatic contract analysis
No public API
Batch upload
Analyze up to 20 contracts simultaneously
One contract at a time in Word
Word integration
DOCX export with tracked changes (native add-in coming soon)
Native Word add-in — works inside Word directly
Pricing transparency
$99/mo Pro, $199/mo Business — public, instant signup
No public pricing — requires sales demo call
Time to start
30 seconds — upload a PDF or DOCX, get results immediately
Requires Word installation, account setup, and potentially a demo call

VERDICT

ClauseGuard wins on features and transparency

Spellbook is a capable Word add-in for lawyers, but it requires a sales call, has no public pricing, and lacks several features ClauseGuard offers out of the box: negotiation simulator, 3-tone redlines, obligation tracking, contract comparison, batch upload, portfolio dashboard, and a developer API. ClauseGuard is transparent — $99/month for Pro, $199/month for Business — and you can start in 30 seconds without talking to sales.

Choose ClauseGuard when:

  • You want transparent pricing without a sales call
  • You need a risk score and structured severity analysis, not just flagged issues
  • You want negotiation simulation that predicts counterparty responses
  • You manage multiple contracts and need portfolio-level analytics
  • You want obligation tracking with automated deadline alerts
  • You need to compare contracts side-by-side
  • You want API access for programmatic integration
  • You work with contracts in PDF format, not just Word

Choose Spellbook when:

  • You work exclusively in Microsoft Word and want inline editing without leaving the app
  • You are a law firm that drafts contracts from scratch and needs real-time suggestions while typing
  • Your organization has an enterprise budget and prefers a sales-led purchase process

Frequently asked questions

Is ClauseGuard more affordable than Spellbook?

ClauseGuard offers transparent pricing: free first analysis, $5 per contract on pay-per-use, $99/month for unlimited Pro, $199/month for Business with team and API access. Spellbook does not publish pricing and requires a sales demo. Based on industry reports, Spellbook pricing typically starts at $300-500/month per user.

Can ClauseGuard replace Spellbook?

For contract review and risk analysis, ClauseGuard offers more features at a lower price point. The main advantage Spellbook has is its native Word integration for real-time contract drafting. If your primary workflow is reviewing existing contracts (not drafting from scratch), ClauseGuard is the stronger choice.

Does ClauseGuard work with Word documents?

Yes. ClauseGuard accepts both PDF and DOCX uploads, and exports analysis results as a Word document with tracked changes that you can send directly to the counterparty. A native Word add-in is also in development.

Which tool has better AI for contract analysis?

ClauseGuard uses a multi-stage Anthropic Claude pipeline specifically calibrated for legal documents, with semantic chunking, parallel analysis, and structured output. Spellbook uses OpenAI GPT-4. Both are capable, but ClauseGuard's pipeline is purpose-built for consistent, structured contract analysis rather than general-purpose text generation.

Try ClauseGuard free

Upload any contract and get a risk score, clause-by-clause analysis, and AI-generated redlines in 90 seconds. No account required.