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Local vs. subscription
Local AI pays for itself on cost only against heavy tiers, or when privacy and unlimited use are the point. Here's the arithmetic, with your numbers.
Mini PC in the listed configuration.
Mini PC in the listed configuration.
$3,499.99 upfront complete-system cost. Electricity assumes the whole computer draws 120.0 W for 4.0 hours per day and 0.0 W for the remaining 20.0 hours, over 30 days at $0.15/kWh. Idle electricity is excluded.
This compares costs, not equivalent capability. Break-even assumes the subscription is cancelled. Tax, shipping, peripherals, maintenance, resale value and financing are excluded. In the chart, Heavy tier means the vendors' high-usage plans (5×, 20× or top tier); Standard tier is the ~$20 plan.
Plan | Price / month | Months | Years |
|---|---|---|---|
| ChatGPT Plus | $20 | 196.2 | 16.3 |
| Claude Pro | $20 | 196.2 | 16.3 |
| Google AI Pro | $19.99 | 196.3 | 16.4 |
| Claude Max (5×) | $100 | 35.8 | 3.0 |
| ChatGPT Pro 100 | $100 | 35.8 | 3.0 |
| Google AI Ultra (5×) | $99.99 | 35.8 | 3.0 |
| Claude Max (20×) | $200 | 17.7 | 1.5 |
| ChatGPT Pro 200 | $200 | 17.7 | 1.5 |
| Google AI Ultra (20×) | $199.99 | 17.7 | 1.5 |
| ChatGPT Pro 500 (top tier) | $500 | 7.0 | 0.6 |
How to read this
Break-even months = hardware cost ÷ (plan price − monthly electricity). Electricity = (load W × load hours + idle W × idle hours) × 30 ÷ 1000 × $/kWh. If electricity costs more than the plan, the rig never pays back.
The brief's worked example: a US$3,499.99 128 GB Strix Halo mini PC at 120 W for 4 h a day and $0.15/kWh costs about $2.16 a month to run. Against a $20 plan that's about 197 months (16 years); against a $200 plan, about 17.7 months.
Cost isn't capability. A local 27B or 120B model is not a frontier model. We'll show a capability ratio (local model score ÷ subscription model score on the same cited index) later; local models' LMArena text scores are now on each model page. Meanwhile, compare like with like: which tasks do you actually need the frontier for?
Plan prices and sources
Plan | USD / month | CAD / month | Source |
|---|---|---|---|
ChatGPT Plus | $20Sourced | CA$28.54Estimate | OpenAI |
Claude Pro | $20Sourced | CA$28.54Estimate | Anthropic |
Google AI Pro | $19.99Sourced | CA$26.99Sourced | |
Claude Max (5×) | $100Sourced | CA$142.71Estimate | Anthropic |
ChatGPT Pro 100 | $100Sourced | CA$142.71Estimate | OpenAI |
Google AI Ultra (5×) | $99.99Sourced | CA$142.70Estimate | |
Claude Max (20×) | $200Sourced | CA$285.42Estimate | Anthropic |
ChatGPT Pro 200 | $200Sourced | CA$285.42Estimate | OpenAI |
Google AI Ultra (20×) | $199.99Sourced | CA$285.41Estimate | |
ChatGPT Pro 500 (top tier) | $500Sourced | CA$713.55Estimate | OpenAI |
US monthly list prices from each vendor's own pricing page, checked 2026-10-12. CAD shown where the vendor page showed it; otherwise USD × 1.4271 (Bank of Canada, 2026-10-09), flagged estimate. Default electricity rate is the brief's example, not a current Alberta tariff. See the builds.