1. Headless CMS — annual licence
Sources: vendor pricing pages (Sanity, Strapi, Storyblok, Contentful), broker aggregators (Vendr, ITQlick, G2). Self-serve and Growth-tier entry points are Confidence A — published rate cards. Enterprise tiers are Confidence B — published but commonly discounted at scale.
Self-serve $1.8k–$12k / yr · Growing team $12k–$60k · Mid-enterprise $60k–$180k · Enterprise $140k–$350k
2. DXP / enterprise platform — annual licence
Sources: Brainvire, 40Q, ITQlick, SaM Solutions, Fishtank — broker and partner commentary. Confidence C across the board. Sitecore, Optimizely, AEM and Acquia are sales-gated; the calculator surfaces a ±40% disclaimer when these vendors are picked.
Entry $45k–$110k · Mid-enterprise $110k–$280k · Global enterprise $280k–$900k
3. Mid-market CMS — annual licence
Kentico Xperience and Umbraco Heartcore publish rate cards Confidence A. Sitefinity and Drupal Enterprise pricing is Confidence C via partner commentary.
Entry $6k–$25k · Standard $18k–$55k · Premium $50k–$150k
4. ECM — annual licence
OnBase per-user pricing comes from ITQlick and SelectHub Confidence B. Deployment-level totals for OpenText, IBM FileNet and M-Files are Confidence C — fully sales-gated.
Departmental $60k–$220k · Mid-enterprise $200k–$800k · Enterprise $600k–$2.5M
5. Implementation cost
SI day rates drawn from ContractorUK Jan 2026, Index.dev European rates 2026, PayScale, Qubit Labs. UK senior consultant £700–£1,300/day; Western Europe €600–€1,200; US $900–$1,800; offshore $250–$550. Confidence B.
Project effort bands from Storyblok migration guide, Dellos, Clear Digital, Webflow Enterprise build cost. Small project 60–150 days; mid-market 300–700; enterprise 1,000–2,500; global enterprise 2,500–6,000+.
Phase split from atechsight 2026, Solutions Review, Ingeniux: discovery 12% · design 20% · build 40% · content migration 12% · testing 7% · training 9%. Always-applied 18% contingency on top. Confidence B.
Scope multipliers: sites = √(sites). Locales = 1 + 0.15 × (locales − 1). Each integration = +5% capped at +40%. Personalisation: light +10%, heavy +25%. Each compliance pick = +3% capped at +15%. Custom legacy migration uplift = +40%. Greenfield skips migration entirely and reduces contingency to 12%.
6. Ongoing run cost
Hosting, content-ops headcount, integration maintenance bundled into size-banded run-cost coefficients (mid-market $60k–$180k / mid-enterprise $180k–$520k / enterprise $500k–$1.8M). Vendor support adds 20% of licence — industry standard. Confidence B.
Out-year enhancement set at 60% of Year 1 implementation, recurring annually from Year 2. Real Story Group's CMS Implementation Cost Curve cites ~100% (i.e. enhancement ≈ original implementation) — we soften to 60% to keep the conservative-defaults principle. Bumps to 75% if 10+ years on legacy. Confidence A for the underlying claim.
7. Benefit-side coefficients
Editor-hour and dev-hour savings, plus revenue uplift, drawn from Forrester Total Economic Impact studies of Contentstack (295% ROI), Kontent.ai (320% ROI) and Storyblok (582% ROI). These are vendor-commissioned composite-organisation studies — directional, not guarantees. Confidence B when used as benchmarks, never as targets. The default conservative case uses the low-end of the published ranges; the TEI toggle multiplies by 2× to surface the vendor-cited case.
8. Risk profile / high-band widening
McKinsey research (via Forecast.app, Runn IT-PM stats 2025) finds that 66% of enterprise software projects overrun, with large project overruns commonly 200–400% over budget. The calculator applies a 1.4× mid → high multiplier by default, and lifts to 1.8× when ANY TWO of: locales ≥ 6, integrations ≥ 5, heavy AI personalisation, ≥ 3 compliance constraints, or 50,000+ pages.
9. Currency
All coefficients are anchored in USD. Display conversion applied at render time: GBP × 0.79, EUR × 0.92. FX rates refreshed quarterly. The single-source coefficient table avoids drift between currencies.
Full source list
The full benchmark research with 40+ source citations lives in the project repo at docs/CMS-IMPLEMENTATION-BENCHMARKS.md. Key analyst sources include:
- • Real Story Group — CMS Implementation Cost Curve
- • Forrester TEI of Contentstack — 295% ROI
- • Forrester TEI of Kontent.ai — 320% ROI
- • Forrester TEI of Storyblok — 582% ROI
- • Brainvire — AEM cost guide for US enterprises 2026
- • ContractorUK — January 2026 market rates
- • Forecast — 66% of enterprise software projects overrun (McKinsey)
Refresh cadence
Coefficients are refreshed quarterly. The model version is shown in the result header — when you see v0.1, the table you're looking at was last reviewed May 2026. We bump the version when any coefficient moves more than 10%.