Illustrative cost

£31,000 to £96,000 ex VAT

Typical
£53,000
Duration
About 18 weeks
Effort
70 to 127.5 days

Illustrative estimate, not a quote. Real prices vary.

Worked out from UK freelance contractor day rates in job adverts, with no consultancy or agency margin added. Consultancies and agencies usually charge more.

Source: IT Jobs Watch. Rates read on ; costs computed on .

What is included

  • Product definition and user research
  • UX design for the core journey
  • Build of a web app with an AI feature at its core
  • Testing, including the AI feature's failure modes
  • Release to early users

Deliverables

  • Working MVP
  • Design files
  • Test report
  • Source code and documentation

Assumptions

  • One core user journey
  • Standard cloud hosting and a commercial model API
  • The client owns the product decisions

Not included

  • Mobile apps
  • Scaling beyond early users
  • Hosting and model fees

Project plan

Phases run one after another, about 18 weeks in all.

Phases, their length and main tasks
PhaseWeeksMain tasks
Discovery and product definition3User interviews; Define the core journey; Technical approach
Design3Wireframes; Prototype testing
Build8Application build; AI feature; Hosting
Testing3Functional testing; AI evaluation
Launch1Release to early users; Measure use

Who does the work

Person-days per role in each phase, low and high effort.

Days by phase and role
PhaseRoleDays (low to high)
Discovery and product definitionProduct manager (AI products)5.5 to 9 days
Discovery and product definitionUX designer3.5 to 7 days
Discovery and product definitionAI architect2 to 5.5 days
DesignUX designer7 to 12.5 days
BuildAI engineer27 to 45 days
BuildGenerative AI (LLM) engineer9 to 18 days
BuildCloud engineer3.5 to 7 days
TestingTest engineer7 to 14.5 days
LaunchProduct manager (AI products)3.5 to 5.5 days
LaunchCloud engineer2 to 3.5 days

How the cost adds up

Cost by role: low, typical and high, before rounding
RoleLow (days × 25th percentile)Typical (days × median)High (days × 90th percentile)
Product manager (AI products)9 × £463 = £4,16811.75 × £550 = £6,46314.5 × £725 = £10,513
UX designer10.5 × £406 = £4,26315 × £450 = £6,75119.5 × £588 = £11,466
AI architect2 × £549 = £1,0983.75 × £650 = £2,4385.5 × £850 = £4,675
AI engineer27 × £488 = £13,17636 × £589 = £21,20445 × £863 = £38,835
Generative AI (LLM) engineer9 × £417 = £3,75313.5 × £543 = £7,33118 × £825 = £14,850
Cloud engineer5.5 × £428 = £2,3548 × £513 = £4,10410.5 × £675 = £7,088
Test engineer7 × £350 = £2,45010.75 × £438 = £4,70914.5 × £588 = £8,526
Total, rounded£31,000£53,000£96,000

How these estimates are worked out

Effort: for each phase we estimate how many days each role works, as a low and a high case. These are our estimates for a typical project of this kind, not measured data.

Rates: each role's daily rate comes from UK contract job adverts over the last six months, as published by IT Jobs Watch. These are freelance contractor rates as advertised, not what was paid, and not what a consultancy or agency charges.

Low end: the low-effort days at each role's 25th-percentile rate. We use the 25th percentile, not the 10th, because the lowest effort at the cheapest rates gives a floor few buyers would ever meet.

Typical: the mid-point between low and high effort, at each role's median rate.

High end: the high-effort days at each role's 90th-percentile rate.

Totals are rounded to the nearest £500 below £10,000 and the nearest £1,000 above, and exclude VAT. Phases run one after another.

Not included:

  • Software licences, model and hosting fees
  • Travel and expenses
  • Your own staff's time
  • A consultancy's or agency's margin, overheads and risk

Real prices vary with the supplier, the state of your data and systems, how much of the work your own team does, where the work happens and how much risk the supplier carries. Consultancies and agencies usually charge more than these contractor rates, and a fixed price usually costs more than time and materials because the supplier takes the risk.

Sources

Source: IT Jobs Watch: UK contract job adverts quoting a daily rate, 6 months to 15 November 2026. Each role's page was read on . Published under CC BY-NC-SA 4.0.

Day rate sources, one row per role, read on 15 November 2026
RoleIT Jobs Watch pageRates quoted25th percentileMedian90th percentile
Product manager (AI products)IT Jobs Watch has no "AI Product Manager" contract title with daily rates; mapped to the closest title, Product Manager.Product Manager360£463£550£725
UX designerUX Designer75£406£450£588
AI architectArtificial Intelligence Architect148£549£650£850
AI engineerArtificial Intelligence Engineer384£488£589£863
Generative AI (LLM) engineerIT Jobs Watch has no "LLM Engineer" or "Prompt Engineer" title with daily rates; mapped to the closest title, Gen AI Engineer.Gen AI Engineer30£417£543£825
Cloud engineerCloud Engineer513£428£513£675
Test engineerTest Engineer245£350£438£588

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