How to Calculate AI Image Credit Costs Before You Buy

The sticker price of a credit pack tells you almost nothing useful. What you need is cost-per-image, and calculating that requires knowing how many images each credit buys at your preferred settings. Here's the method that works across platforms. ## The Core Formula Cost per image = (Pack price) / (Credits in pack) x (Credits per image) Or more practically: figure out your effective cost per image at your preferred resolution and settings, then compare across platforms. ## Platform Credit-to-Image Rates **Midjourney** - Subscription-based, not credit-per-image. Basic plan (~$10/month) gives roughly 200 image generations. Fast hours matter more than raw image count. **NovelAI** - Anlas cost 3-6 per standard image, 12-16 per high-resolution. Opus tier ($25/month) includes 10,000 Anlas, so roughly $0.0025 per standard image - extremely cheap at scale. **Stable Diffusion (self-hosted)** - Effectively $0 per image if you have the hardware. Cloud-hosted variants charge by generation; expect $0.01-0.03 per image on most providers. **NSFW credit platforms** (Unstable Diffusion, Pornderful, etc.) - Usually $0.05-0.15 per high-quality image at retail credit prices. Subscription tiers bring this to $0.02-0.05. ## What Affects the Per-Image Rate - **Resolution**: doubled resolution typically quadruples compute cost and thus credits - **Sampling steps**: more steps = better quality = more credits per image - **Model type**: SDXL and higher-end models cost 2-3x more per image than SD 1.5 - **Upscaling**: post-generation upscaling is a separate credit cost on most platforms ## Practical Buying Guide 1. Generate 10 test images at your usual settings and note the credit cost 2. Divide pack price by credits to get cost-per-credit 3. Multiply credits-per-image by cost-per-credit to get your real per-image cost 4. Compare across pack sizes - the largest pack is almost always 30-50% cheaper per image