When SaaS wins
- Monthly ticket volume under 15K.
- Tier-1 dominant (complexity < 20%).
- Single language.
- Non-regulated industry.
- Standard helpdesk integration (Zendesk, Freshdesk, Intercom).
When custom wins
- Volume over 30K monthly tickets.
- High complexity (≥30% complex tickets).
- Regulated industry (banking, insurance, healthcare, legal, government).
- 6+ supported languages.
- Workflows that are core IP.
When hybrid is the answer
Mid-range scenarios — moderate volume, mixed complexity, 3-5 languages. Use SaaS for tier-1 deflection and a custom build for tier-2 / tier-3 workflows that touch your IP-sensitive systems.
7-step framework
The calculator runs each input through this rubric and produces a verdict in 60 seconds. The rubric is published below; every threshold is editable in the source.
- Get the volume baseline — Pull the last 12 months of monthly tickets and the year-over-year growth rate.
- Score regulated risk — Healthcare, fintech, legal - SaaS often wins on compliance certifications. Custom may win when sovereign data residency or unique compliance frameworks apply.
- Score IP sensitivity — If your support workflows or knowledge base are a competitive advantage, custom may win. Otherwise SaaS is fine.
- Compute SaaS year-3 cost — Per-resolution or per-seat × 3 years + integration ($25K-$35K one-time) + tokens (10-15% of gross savings).
- Compute custom year-3 cost — Build cost ($40K-$180K) + tokens (similar) + ops + ongoing engineering × 3 years.
- Apply the decision rubric — SaaS wins if year-3 SaaS < year-3 custom + 25% buffer. Custom wins above 30% complexity, 6+ languages, or in regulated industries.
- Document the decision — Capture rationale and revisit annually - vendor capabilities and your volume both move quickly.
Callout
Distribution disclosure
buzzi.ai builds custom chatbots for a living. To prove the recommendation engine isn't biased toward our commercial interest, we run a CI test on every change: 50 synthetic inputs, SaaS must be the recommendation in ≥40% of cases. Current distribution: SaaS 74%, Custom 6%, Hybrid 20%.
Try it on your numbers
Plug in your real volumes and see the projection.
The calculator runs the same methodology described above — channel modifiers, hidden costs, and the build-vs-buy verdict. Free preview without an email.
Run the calculatorFrequently asked
Is the recommendation deterministic?
Yes. Same inputs always produce the same recommendation. There is no LLM scoring loop.
How is the SaaS≥40% gate enforced?
CI runs distribution-bias.test.js on every change. If SaaS share drops below 40%, the build fails.
Can I see the source for the rubric?
Yes - app/lib/tools/cs-savings/build-vs-buy.js. Every threshold is editable.