OpenAI image token calculator
Estimate how many input tokens an image costs on OpenAI / ChatGPT (GPT-5 family), and whether packaging your prompt as an image beats sending it as text.
| Model family | Image tokens (est.) | vs 2,000 text tokens |
|---|---|---|
| OpenAI | ~256 | 87% fewer tokens |
Formulas: OpenAI — ≈ one token per 32×32-pixel patch (rounded up per side). Estimates only, before any wrapper instructions or caching — verify with the provider's token-counting API. See our methodology.
Common sizes on OpenAI
| Square image | Estimated tokens | Beats text longer than |
|---|---|---|
| 384×384 | ~144 | ~144 text tokens |
| 500×500 | ~256 | ~256 text tokens |
| 512×512 | ~256 | ~256 text tokens |
| 768×768 | ~576 | ~576 text tokens |
| 1024×1024 | ~1,024 | ~1,024 text tokens |
Notes and caveats
Older tile-based OpenAI families (GPT-4o era) use a different calculation — a base cost plus a per-512-pixel-tile cost that depends on the detail setting — so the same image can be billed very differently across model versions. Always check the model you actually call.
OpenAI also resizes large images before processing. Oversized canvases may be downscaled, which reduces both the token count and the legibility of small text — cheaper is not automatically more readable.
These are input-side estimates before wrapper instructions, caching, latency, retries and accuracy effects. Token rules are model-version-specific and change — verify with the provider's token-counting endpoint, and read when not to convert prompts to images before shipping this in production.
Try it on a real prompt
The visual prompt compressor gives you a live OpenAI-specific estimate, flags exact identifiers that shouldn't go into a lossy image, and exports the PNG plus the original .txt — all locally in your browser.
Last updated July 15, 2026 · Estimates are derived from provider documentation and can change — see methodology.