Which is cheaper, GPT-5.4 Image 2 or GPT-Realtime-2.1?

GPT-Realtime-2.1, at $36 per million tokens against $39 for GPT-5.4 Image 2, three parts input to one part output, read on 16 Sept 2026.

Where is each one cheapest?

GPT-5.4 Image 2: nobody goes below the maker's own price with a reason we can point at, so $39 is the number to beat. GPT-Realtime-2.1: nobody goes below the maker's own price with a reason we can point at, so $36 is the number to beat.

Can I buy both from one provider?

Yes. One provider sells both: OpenAI. The cheapest of them for the two together is OpenAI.

Which holds more context?

GPT-5.4 Image 2, at 272k tokens against 128k.

GPT-5.4 Image 2 vs GPT-Realtime-2.1.

model vs model · prices as of 16 Sept 2026

GPT-5.4 Image 2 and GPT-Realtime-2.1 split the 5 rounds this table counts: the two list price rows, the cheapest price we can explain, the standard price and context. The weighting you pick decides the rest.

OpenAI

GPT-5.4 Image 2

$39/M tokens

OpenAI list price, nothing below it is accounted for · $5.70 per 1,000 pages

272k context · reads images

OpenAI

GPT-Realtime-2.1

$36/M tokens

OpenAI list price, nothing below it is accounted for · $3.84 per 1,000 pages

128k context · tool calling · reads images

List price in (lower wins)

$8/M

$4/M

List price out (lower wins)

$15/M

$24/M

Cheapest we can explain (lower wins)

none below list

Standard price (lower wins)

$39/M

$36/M

Cost per 1,000 pages (lower wins)

$5.70

$3.84

Context

272k tokens

128k tokens

Open weights

not stated

Tool calling

yes

Structured output

yes

Reads images

yes

Reasoning

yes

Released

21 Apr 2026

6 Jul 2026

Providers selling it

Price we measure against

the maker's own

Trains on your prompts (no is better)

no provider to check

Providers selling both · 1

OpenAI$39 / $36

GPT-5.4 Image 2 then GPT-Realtime-2.1, per million tokens

Go further

open in the compare tool →every price for GPT-5.4 Image 2 every price for GPT-Realtime-2.1

Add a third or fourth model, or switch the weighting, in the tool.

Frequently asked

Which is cheaper, GPT-5.4 Image 2 or GPT-Realtime-2.1?: GPT-Realtime-2.1, at $36 per million tokens against $39 for GPT-5.4 Image 2, three parts input to one part output, read on 16 Sept 2026.
Where is each one cheapest?: GPT-5.4 Image 2: nobody goes below the maker's own price with a reason we can point at, so $39 is the number to beat. GPT-Realtime-2.1: nobody goes below the maker's own price with a reason we can point at, so $36 is the number to beat.
Can I buy both from one provider?: Yes. One provider sells both: OpenAI. The cheapest of them for the two together is OpenAI.
Which holds more context?: GPT-5.4 Image 2, at 272k tokens against 128k.

Prices exclude tax and are per million tokens, read 16 Sept 2026 from each provider's own catalog. The standard price blends three parts input to one part output; a page is 600 tokens in and 60 out. Bars are scaled to the larger value in each row.