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Inference pricing · TypeSafe AI

What Jev's price card implies

TypeSafe AI sells Jev at $0.042 per million input tokens, output free. That is a linear price. The cost underneath it is not.

A published price is a constraint. It has to cover the FLOPs the model burns, on hardware you can actually rent, or it is a subsidy. Working backwards from $0.042 per million input tokens tells you roughly how big the model can be, and — more interestingly — which workloads a flat per-input-token price cannot cover at any model size.

Three things move the answer. Weights cost 2P FLOPs per token slot. Attention adds 4·L·d·n_layers, which grows with the context, so cost is quadratic in document length where revenue is linear. And Jev answers N questions per document against a published price that never says which side of “input tokens, output free” a typed question falls on — a definition worth more than it sounds. The panel below is that arithmetic; the figures are the same model swept along one axis at a time.

The model

The workload

Share of the stack a question slot traverses. 1.0 treats it as a full token slot; lower models a thin cross-attention readout head. Unpublished — this is the widest assumption on the page.

The rig

Billing

Uncheck if only the document counts. The price card says “input tokens, output free” without saying which side the questions fall on.

Gross margin

Revenue / call
GPU cost / call
FLOPs / call
Attention share

01The cost basis sets a ceiling on model size

A rented accelerator converts dollars into FLOPs at a fixed rate. Peak dense throughput, derated by the fraction you actually achieve, divided into the hourly price:

c_flop = ($/GPU-hr ÷ 3600) ÷ (peak_FLOPS × MFU)

At the default rig that is about 1.25e-18 dollars per FLOP. Revenue is 4.2e-8 dollars per input token. Divide and you get the compute budget a single token can pay for: roughly 3.4e10 FLOPs. A dense forward pass spends 2P of those in the weights, so at break-even P = 1.7e10 — about 17B parameters. FP8 roughly doubles it.

That is a ceiling at zero margin. A business wanting 80% gross margin on inference has to fit in a fifth of it, which lands in the low single-digit billions. The price card is not consistent with a 70B model under any rental price currently on the market; it is very consistent with something small, which is exactly what you would build if you wanted one parallel pass in under 500ms.

Fig 1Margin vs parameter count
H100 BF16 H100 FP8 B200 FP8 Break-even
Model, not measurement. Swept at the current document length and question count; the hollow marker is your panel setting. Curves use each combination's own list price, so they also carry the rental market's pricing, not just silicon.

02Attention is quadratic; the price is linear

The weights term is not the whole cost. Attention over a context of L tokens contributes 4·L·d·n_layers FLOPs per slot, so the cost of a document is:

FLOPs(doc) = 2·P·L + 4·L²·d·n_layers
Revenue(doc) = L × $4.2e-8

Revenue has one power of L. Cost has two. There is therefore a document length past which every additional token is sold below cost, and it does not depend on how the product is marketed — only on shape:

L* = (price ÷ c_flop − 2P) ÷ (4 · d · n_layers)

For the default 3B model on H100 BF16 that crossover sits near 87k tokens. FP8 pushes it to roughly 192k. Neither number is anywhere near the context lengths a document-analysis product invites you to use. Send a 500k-token contract and the call loses money by construction, no matter how many questions you ask or do not ask.

Note what hardware does and does not fix. B200 buys roughly 2.3x the FLOPs at roughly 2.5x the hourly rate, so at these list prices its dollars-per-FLOP is actually slightly worse than an H100 — 6.9e-19 against 6.2e-19 at FP8. Newer silicon does not move this wall. Precision does, and it is the only lever on the page that buys a full doubling.

Fig 2Margin vs document length
H100 BF16 H100 FP8 B200 FP8 Break-even
Model, not measurement. Swept at the current parameter count and question count. The fall-off is the L² attention term overtaking the linear price; on a log-log axis a quadratic cost against a linear price is a straight descent.

03The question slots hinge on one undefined word

The obvious guess is that question slots are where the money leaks: Jev answers N questions per document, output is free, so surely N is unpriced compute. Work it out and the guess is wrong, in a way that turns out to be more interesting.

At full depth a question slot is arithmetically identical to a document token. It traverses the same stack, it attends over the same L positions, so it costs 2P + 4·L·d·n_layers — exactly what a document token costs. And if it bills as an input token, it earns exactly what a document token earns. Cost and revenue scale together, so the margin does not move at all:

margin = revenue ÷ cost = price ÷ (perSlot × c_flop)
  — no N in it, at depth 1.0 with questions billed

That is why the boundary in Fig 3 is a vertical line at the default settings. Asking one question or ten thousand changes nothing. The whole exposure is in L, which is section 02's problem, not a new one.

The neutrality rests entirely on a word the price card never defines. It says input tokens, output free. A typed question is neither, obviously: it is something you send, that produces something you receive. If questions bill as input, N is free of consequence. If they are treated as part of the decision output — free — then every question slot is pure unpriced compute, and N tilts the boundary hard. Untick the billing box in the panel: an 8k-token document with 5,000 questions goes from a 3.9x margin to 0.65x, without changing anything else.

This is also where the amortization story has to pick a side. Jev's cost claim needs many questions per document — that is what spreads the encode. But each question either bills, in which case it is just input tokens and the “output free” framing is doing no work at all; or it does not, in which case the cheapest workloads for a buyer are the ones that lose the most money for the seller. There is no third option, and the price card does not say which one it is.

Fig 3Break-even surface over document length and question count
Above cost Below cost Break-even boundary
Model, not measurement. Shading is the margin ratio at the current parameter count and rig; the boundary is where revenue equals GPU cost, and everything right of it is served below cost. The hollow marker is your panel setting. At the defaults the boundary is vertical — N does not move it. Untick question tokens bill as input, or drop the slot depth below 1.0, and it tilts.

04Where this lands

None of this says the price is wrong. Flat prices are a product decision, and a seed-stage lab pricing below cost to buy adoption is ordinary — the number on the card tells you what they want the workload to cost a buyer, not what the GPU does. What the arithmetic does say is narrower and more useful:

The price bounds the model. At $0.042 per million input tokens, a profitable Jev is small — low single-digit billions of parameters. That is consistent with the latency claim and inconsistent with "frontier-scale". It also means the comparison that matters is against a fine-tuned cross-encoder, not against a chat model doing classification.

The price cannot survive long context. A linear per-input-token price against a quadratic attention cost has a crossover, and for a model this size it arrives well before the context lengths document workloads use. Expect a length cap, length-tiered pricing, or a quiet repricing.

One undefined word carries the rest. Whether a typed question bills as an input token decides whether N is free of consequence or the whole exposure. The published card does not say. That is not a rounding error in a pricing page; it is the difference between a neutral axis and an unbounded one, and it is the first question worth asking them.

The practical read for a buyer is the inverse of all this. Jev's price is a genuine bargain on short documents with many questions — and that is also the regime where a self-hosted cross-encoder is cheapest to run yourself, because the encode you are amortizing is small either way. The place you would most want a hosted model to save you, long documents, is the place this price cannot survive. Price your own workload at both ends before you join the waitlist.

05Assumptions

QuantityValue usedWhy, and how wrong it could be
Jev price$0.042 / M inputPublished on typesafe.ai, September 2026. Output stated free.
H100 SXM989 / 1979 TF, $2.00/hrDense BF16 / FP8, no sparsity. Rental price varies 1.5–3 by provider and commitment.
H200 SXM989 / 1979 TF, $2.50/hrSame compute as H100, more HBM. Memory headroom does not change these FLOP sums.
GH200989 / 1979 TF, $2.20/hrHopper GPU beside Grace. Priced as a superchip node.
B2002250 / 4500 TF, $5.00/hrDense. Rental pricing is still thin and moves fast; this is the softest cell in the table.
MFU0.45Prefill is compute-bound and batches well, so this is achievable but optimistic at long context.
Model shapeP = 12·n·d², d/n = 128Standard aspect ratio. Reproduces Llama-7B and -70B shapes to within a few percent.
Attention4·L·d·n per slotFull dense attention. Sliding-window, GQA on the KV side, or any sparsity pushes the wall right — this is the most consequential simplification here.
Question costdepth × full slotJev's architecture is unpublished. Exposed as a knob for that reason; at depth 1.0 a question is a full token slot.
Excluded—KV cache reuse across calls, batching inefficiency, serving overhead, networking, storage, idle capacity, and any margin on hosting. The first helps them; the rest hurt.

Everything above is an analytical model built from published prices and public hardware specifications. No part of it is a measurement of Jev, which is in gated early access. Where a number could not be sourced it became a control in the panel rather than a hidden constant.

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