Luminance vs Spellbook: Enterprise Diligence vs Word-Native Drafting
Luminance and Spellbook both work with contracts but solve different problems. Luminance is an enterprise contract analysis platform for diligence and large-scale review at AmLaw firms and global corporations. Spellbook is a Microsoft Word add-in for drafting and reviewing contracts inline, designed for individual transactional lawyers and small-to-mid-size firms. Comparing these is comparing a fleet truck to a car — different tools for different jobs.
Last reviewed: 2026/05/18
Luminance
Enterprise AI for portfolio-level contract analysis and institutional memory.
Spellbook
AI contract drafting and review inside Microsoft Word for transactional lawyers.
5-Dimension Scorecard
Scores 1–5 with 0.1 precision. Bars highlight the higher score per dimension. Hands-on review pending; scores reflect industry consensus.
Feature Comparison
| Feature | Luminance | Spellbook | Note |
|---|---|---|---|
| Microsoft Word native add-in | |||
| Enterprise contract diligence | |||
| Novel contract type handling (unsupervised AI) | |||
| Individual lawyer drafting | |||
| Playbook enforcement | Different scales | ||
| Solo / small-firm pricing | |||
| UK / European market presence | Luminance stronger | ||
| Enterprise scale diligence |
Pricing
Luminance: enterprise pricing, custom quotes typically $50,000-150,000+/year. Spellbook: $99+/user/month individual; enterprise custom. Different orders of magnitude reflecting different scopes.
User Reviews
Luminance
Luminance: enterprise customer base. Reviews emphasize novel contract type handling and UK/EU market depth. Critical reviews note US market penetration smaller than Kira.
Spellbook
Spellbook: 150+ G2 reviews. Praise: Word integration, learning curve, individual lawyer pricing. Critical: occasional generic suggestions, prompt phrasing matters.
When to pick Luminance
Luminance works for AmLaw diligence teams, large legal departments, and any firm that regularly reviews 100+ contracts in a matter. The supervised + unsupervised AI hybrid handles novel contract types without extensive pre-training. Strong in UK and European markets.
When to pick Spellbook
Spellbook works for individual transactional lawyers and firms under 50 attorneys that draft contracts in Microsoft Word. Real-time clause suggestions and playbook enforcement integrate into the drafter's existing workflow.
Frequently Asked Questions
- Does Spellbook do diligence?
- Spellbook is built for individual contract drafting and review, not batch diligence on large contract populations. For diligence at scale, Luminance or Kira are better fits.
- Does Luminance work in Word?
- Luminance offers some Word integration but is primarily web-based. It's less Word-native than Spellbook, reflecting the enterprise diligence vs individual drafting focus.
- Which for an in-house transactional team?
- Depends on volume. High-volume teams (large enterprises with extensive contract operations) often need both: Spellbook for drafting, Luminance or Kira for diligence and intake review.
- AI methodology comparison?
- Luminance uses supervised + unsupervised AI for contract analysis at the document set level. Spellbook uses LLM-based drafting suggestions at the clause level. Different problems, different AI approaches.
- Which is cheaper?
- Spellbook at $99/user/month is the lower entry point. Luminance enterprise pricing starts an order of magnitude higher. Different products for different buyers.
Our take
If you're doing diligence at scale, Luminance. If you're drafting and negotiating contracts in Word, Spellbook. These tools rarely compete head-to-head — firms that need both buy both.
Last reviewed: 2026/05/18. Hands-on review pending. Scores reflect industry consensus. LawyerAI does not accept affiliate commissions; Featured placement is clearly labeled and does not influence editorial scores.