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Break-even Board

Plug in your numbers, watch the break-even cross.

Break-even Board

AvailableFree
  • Prompting$1,000/mo✗ accuracy
  • RAG$900/mo✓ pick
  • Fine-tuning$5,150/mo
Your crossover, not a hot takethe right answer flips with your numbers

At 50K queries/mo, 85% accuracy and 2000ms, the cheapest strategy that qualifies is RAG at $900/mo. Prompting and RAG cross at 41.7K queries/mo; RAG and fine-tuning cross at 900K.

“Fine-tune vs prompt” has no fixed answer — it’s a crossover between fixed cost and per-query cost, gated by your accuracy and latency needs. Prompting wins at low volume; RAG and fine-tuning earn their setup cost only once volume (or the accuracy bar) is high enough. Compute your own line before you copy someone’s.

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Break-even board

Set your own task profile — monthly query volume, required accuracy, latency budget — and three cost curves for prompting, RAG, and fine-tuning plot against volume with a marker on exactly where your numbers land. Drag the accuracy bar and the "right" strategy visibly flips. It replaces fine-tune-vs-prompt hot takes with your own crossover math. Runs entirely in your browser (0 uploads, works offline).

How to use it

  1. Set your monthly volume, accuracy requirement, and latency budget.
  2. Watch the three cost lines and where your volume marker crosses them; disqualified strategies (too low accuracy, too slow) are flagged.
  3. Read the recommendation and the X-ray: the cheapest qualifying strategy for your numbers, and the exact volumes where the answer flips.

What this clears up (the fundamentals)

  • It's a crossover, not a rule — each strategy trades fixed cost (setup / training) against per-query cost. Prompting has no fixed cost but pays the most per call; fine-tuning is the reverse.
  • Volume decides the winner — at low volume, prompting's zero setup wins; as volume rises, RAG then fine-tuning earn back their fixed cost through cheaper queries.
  • Requirements gate the options — accuracy and latency ceilings can disqualify a strategy entirely, flipping the answer regardless of cost.
  • The answer is personal — the same "just fine-tune it" advice is right for one team and wrong for another; only your own volume and requirements settle it.

Where it's used

An AI build-vs-buy decision tool — the fastest way to cut through "you should fine-tune" / "just prompt it" debates with a number that's actually yours. It's a miatz build-lab concept playable; learn to build it yourself.

FAQ

How is each strategy's cost computed?

Fixed cost plus per-query cost times volume. Prompting has zero fixed cost but the highest per-query price; RAG adds a setup cost for a cheaper query; fine-tuning has the largest fixed (training) cost and the cheapest queries.

What does "disqualified" mean?

A strategy is removed from the running if it can't reach your required accuracy or can't respond within your latency budget — even if it would be the cheapest, it doesn't qualify.

What's a crossover volume?

The volume at which two strategies cost exactly the same. Below it, the lower-fixed-cost option is cheaper; above it, the lower-per-query option pulls ahead. The tool marks the two key crossovers.

Is anything uploaded?

No. All the cost math runs in your browser — nothing is transmitted or stored. Turn off your Wi-Fi and it still works.

Limits

A teaching model with three preset strategies and linear costs — real decisions include quality variance, maintenance, vendor lock-in, and data-availability constraints. Use it to build the crossover instinct, then plug in your own vendor quotes.

Related

Part of the Demystify Playgrounds. Explore the rest from the Playgrounds home.

Bookmark this page (Ctrl+D, or ⌘D on Mac) — it works offline the next time you need it.

Ninety playgrounds. Zero setup.

Every concept here is playable free, no account — and inside the program you learn to rebuild the machinery yourself.