Question 1

How is video billed when you send it to an LLM?

Accepted Answer

A multimodal model does not watch video the way a person does — it samples frames, usually about one per second, and treats each frame as an image made of tokens, then adds the audio track as its own stream of tokens. So the input cost is the number of sampled frames times the tokens per frame, plus audio tokens, plus your text prompt. Gemini bills roughly 258 tokens per second of video at default resolution and around 32 tokens per second of audio; with GPT-4o you extract frames yourself and each tiled frame runs from about 85 to over 1,000 tokens depending on detail. Either way, video is by far the most token-hungry input modality, which this calculator makes concrete.

Question 2

Why is a one-hour video so expensive to analyse?

Accepted Answer

Because the tokens scale with the length of the footage. At one frame per second and 258 tokens per frame, an hour of video is 3,600 frames and about 929,000 image tokens, plus roughly 115,000 audio tokens — well over a million input tokens for a single video, before the model writes a word of answer. At a few dollars per million input tokens that is a meaningful bill per video, and it multiplies fast across a library. The calculator shows the tokens per video, the cost per video, and the monthly total so a one-off experiment does not turn into a surprise at scale.

Question 3

How do I make video understanding cheaper?

Accepted Answer

The biggest lever is frame rate: sampling at one frame every two or five seconds instead of one per second cuts image tokens proportionally, and for slow-moving footage — a lecture, a security feed, a screen recording — it rarely loses anything that matters. Dropping the audio track when you only need the visuals, or transcribing audio with a cheap speech-to-text model and feeding the transcript as text instead of paying audio-token rates, is another large saving. Lowering frame resolution reduces tokens per frame, and clipping to the relevant segment rather than sending the whole file is the simplest win of all. The frame-rate table on this page shows exactly how much each setting moves the bill.

Question 4

Is it cheaper to transcribe the audio than to send the whole video?

Accepted Answer

Very often, yes, if your question is about what is said rather than what is shown. Speech-to-text models charge per minute of audio at a fraction of a cent, and the resulting transcript is a few thousand text tokens for an hour of speech — orders of magnitude cheaper than paying image-token rates on a frame every second. Send the full video only when the visual content genuinely matters; for talking-head footage, meetings, and podcasts, transcribe first and reason over the text. This calculator lets you set audio tokens to zero to model the transcript route and compare it against sending the frames.

コスト計算を理解するビデオ

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よくある質問

ビデオを LLM に送信すると、どのように請求されますか?

1 時間のビデオの分析にこれほどコストがかかるのはなぜですか?

ビデオ理解をより安価にするにはどうすればよいですか?

ビデオ全体を送信するよりも、音声を文字に起こした方が安くなりますか?