Industry · Legal

Quantify the real cost of AI-enabled contract review, drafting and research across an entire law firm.

Legal AI workloads are among the most context-heavy in the enterprise — contracts, case law, and discovery sets routinely push 50K–200K input tokens per interaction. This calculator models annual AI OpEx for partners, associates and paralegals across the firm.

Tokens / attorney / yr

25–90M

Document-heavy workflows

Annual cost / attorney

$200–$2,200

Frontier model usage

Input / output split

90% / 10%

Highest in the enterprise

Peak doc context size

100K+ tokens

Per contract review

Run the numbers for your team

Open full calculator →

Calculator

Configure your team

Embedded in core workflows. Mixed adoption.

AI-assisted tasks

3 / 3

Annual estimate

$23.1K

Total token OpEx for 150 employees · Claude Sonnet 4

Tokens per employee / year36.65M
Total tokens / year5.50B
Input tokens4.95B90%
Output tokens549.75M10%
Cost per employee / year$153.93
Avg daily tokens / employee157.5K
Blended price$3.00 in · $15.00 out / 1M tokens
Working days assumed220
Task coverage100%

Key cost considerations for legal

  • Confidentiality requirements push many firms toward private deployments — factor in 1.5–3x cost premium.
  • Long-context models (Claude Sonnet, Gemini 2.5 Pro) reduce chunking overhead and total tokens consumed.
  • Citation-grounded RAG indexing should be modeled as a persistent annual baseline.
  • Senior partner review uses high-end models sparingly but reliably — keep frontier capacity available.

Primary AI workloads in this industry

Frequently asked questions

How much does AI cost per lawyer per year?

Mid-sized firms report $200–$700 per attorney per year on balanced models, rising to $1,500–$2,200 when frontier models like Claude Opus 4 are used for complex matter analysis.

Which AI model is most cost-effective for legal work?

Claude Sonnet 4 and Gemini 2.5 Pro offer the best balance of long-context reasoning and price for contract review. Reserve Claude Opus 4 or GPT-5 for novel legal questions where accuracy materially affects outcomes.

Related calculators and guides