
AIHubMixOn Artificial Analysis' Intelligence Index, one Gemini 4 Argon task costs $1.99 at the launch price...
On Artificial Analysis' Intelligence Index, one Gemini 4 Argon task costs $1.99 at the launch price and $3.98 at the standard price. On the Vals Index, run at standard prices, it costs $15.68 per test, rising to $193.78 on a long computer-use benchmark.
Those are the numbers to size budgets, spend caps and rate limits around, not the $2/$10 headline. The engineering problem is that you have to plan before you can call the model, with part of the price list still unpublished. This post lays out the measured per-task costs, explains why the per-token discount doesn't carry through, walks through the billing failure modes that break a budget, each with a fix, and ends with a small calculator for your own token counts. Inputs Google hasn't published are marked TBD.
Argon's prices come from Google's launch post; the other Gemini rows come from the Gemini API pricing page. USD per million tokens.
| Model | Input | Cached input | Output |
|---|---|---|---|
| Gemini 4 Argon, promo | $2.00 | $0.10 | $10.00 |
| Gemini 4 Argon, standard | $4.00 | TBD | $20.00 |
| Gemini 3.1 Pro Preview | $2.00 | $0.20 | $12.00 |
| Gemini 3.8 Flash, to Dec 31 | $0.75 | $0.075 | $3.75 |
| Gemini 3.8 Flash, from Jan 1 | $1.50 | $0.15 | $7.50 |
| GPT-6 Astra | $10.00 | ā | $50.00 |
Figures in this section come from Artificial Analysis (its launch analysis and model pages) and Vals AI. Both ran Argon at high, its highest reasoning setting. Neither is Google's own number.
Artificial Analysis runs every model through the same Intelligence Index tasks and reports the average cost of one task. It doesn't say how many tasks the index has.
| Model | Index score | Cost per task |
|---|---|---|
| Gemini 4 Argon (high), promo | 53 | $1.99 |
| Gemini 4 Argon (high), standard | 53 | $3.98 |
| GPT-6 Astra (max) | 53 | $3.26 |
| Gemini 3.1 Pro Preview | 30 | $1.30 |
Vals AI ran Argon at the standard $4/$20 price, with temperature 1 and a 262,144-token output cap, and reports the average cost of one test.
| Model | Vals Index | Cost per test |
|---|---|---|
| Gemini 4 Argon | 68.90% | $15.68 |
| Claude Sonnet 5.5 | 67.04% | $21.34 |
| Claude Opus 5.5 | 66.97% | $32.14 |
| Claude Fable 5.1 | 65.83% | $28.71 |
Even at standard prices, Argon costs less per test on this suite than the three Claude models just below it. The cost climbs on Vals' long agentic benchmarks:
| Vals benchmark | Argon score | Cost per test |
|---|---|---|
| CUA-bench | 4.83% | $193.78 |
| Code Migration | 68.17% | $57.82 |
| Terminal-Bench Science | 44.29% | $44.90 |
| SRE Bench | 44.28% | $30.45 |
CUA-bench, a computer-use benchmark, is the worst case: the most expensive test in the set and one of Argon's weakest results, 7th of the 8 models Vals ran.
Cause: the budget was set at $2/$10, and the promotion has no announced end date. When it ends, the same traffic spends twice as fast.
Fix: budget at $4/$20 from day one and treat the promotion as a bonus.
Cause: Argon's output limit is 1M tokens. An uncapped answer that runs to the limit costs $10 at promo prices and $20 at standard.
Fix: set an output cap on every request, sized to the job, instead of leaving the 1M ceiling open.
Cause: Argon writes long: about 62k output tokens per Artificial Analysis task, 2.3 times GPT-6 Astra's 27k. On Gemini 3 models, Google also bills output "including thinking tokens". Argon isn't on Google's pricing page yet, so that's worth confirming for Argon.
Fix: fix the thinking level per workflow, and budget output tokens for the reasoning, not just the answer.
Cause: the AIHubMix Gemini guide notes that an implicit cache hit needs the same content, model and parameters, with repeated context placed first. Changing the thinking level mid-session or reordering the prompt between turns turns cached input back into full-price input.
Fix: put stable context first and keep it identical from turn to turn: system prompt, tool definitions and documents at the top, the user's new message last. Don't switch thinking levels mid-session.
Cause: Argon declines more often than other frontier models when it isn't sure. A declined answer still bills its input and thinking tokens, and retrying the same question on Argon pays again.
Fix: route declines to a person or another model rather than retrying Argon.
Cause: Long Decode Continuation pauses long answers and resumes them across follow-up calls. How those calls are billed, and whether earlier output is counted again as input, isn't documented. [TBD: Long Decode Continuation billing]
Fix: none confirmed yet. The per-request output cap still bounds each call.
Cause: every step of the agent runs on Argon, including extraction and formatting.
Fix: route by difficulty. Send extraction, classification and formatting to Gemini 3.8 Flash and keep Argon for the hard reasoning steps. Gemini 3 models also get 50% off through the Batch API; Argon's batch rate is TBD, so re-check when it appears.
Prices go in a dict, and the standard cached rate is an argument because nobody has published it. Plain Python, no dependencies. Feed it token counts you measured yourself.
PRICES = { # USD per 1M tokens
"promo": {"input": 2.00, "cached": 0.10, "output": 10.00},
"standard": {"input": 4.00, "cached": None, "output": 20.00}, # cached rate TBD
}
def task_cost(uncached_in, cached_in, output, tier="promo", cached_rate=None):
p = PRICES[tier]
cached = p["cached"] if p["cached"] is not None else cached_rate
if cached is None:
raise ValueError("Pass cached_rate: Argon's standard cached price isn't published yet")
return (uncached_in * p["input"] + cached_in * cached + output * p["output"]) / 1_000_000
# Use token counts from your own logs, e.g. the usage field of the same workflow
# run on Gemini 3.8 Flash: task_cost(uncached_in, cached_in, output, "promo")
Measure real token counts on Gemini 3.8 Flash or 3.1 Pro Preview through AIHubMix and feed them into task_cost. Expect Argon's to be higher: on Artificial Analysis' index it generated 110M output tokens where Gemini 3.1 Pro Preview generated 67M. Treat the result as a floor, not a forecast.
Argon has a model page on AIHubMix, but it's marked coming soon and its AIHubMix price isn't set yet. [TBD: AIHubMix price for Gemini 4 Argon]
Until then, Gemini 3.8 Flash is the cheapest way to prototype the same workflow and collect token counts. Argon's price will appear on its model page once it's set.