NanoGPT works on a prepaid balance. You add $5+ and each prompt costs based on token usage. GPT-3.5 Turbo is basically free; GPT-4o runs a few cents per prompt. I spend around $6-8/month using it daily for coding and writing. Casual users probably spend less than a cup of coffee.
The Basic Idea
NanoGPT works on a prepaid balance model. You add funds, then each prompt you send costs based on how many tokens it uses. How much depends on the model. GPT-3.5 Turbo is fractions of a cent per prompt. GPT-4o or Claude 3.5 Sonnet cost more, think a few cents, but they're noticeably better at complex tasks.
I started using this back in March 2026 after getting tired of paying $20/month to ChatGPT even during weeks where I barely used it. The pay-per-prompt model just makes more sense for how I work.
What You Get
- ✓No lock-in — only pay when you actually use it
- ✓Cost shown upfront — you see the price before every prompt
- ✓Spend limits — set daily or monthly caps
- ✓Switch models freely — GPT-4, Claude, Gemini from one account
- ✓OpenAI-compatible API — works with SillyTavern and other tools
Token Pricing Explained
AI models process text in chunks called tokens. One token is roughly 0.75 English words, so a 200-word prompt is about 267 tokens. Both your input and the AI's response count toward the total. That's what you're charged for.
You see the estimated cost before you hit send. No hidden fees, no markup on top of the raw token price, no minimum charge. If your prompt costs $0.003, that's what you pay. I've had prompts that cost $0.0004. Literally less than a penny.
One thing that caught me off guard at first: the token count can be surprisingly high for long conversations. A back-and-forth debugging session with GPT-4o can run $0.30-0.50 depending on how deep you go. Still way cheaper than a $20 subscription for the same work, but worth knowing.
| Model | Input (per 1K tokens) | Output (per 1K tokens) |
|---|---|---|
| GPT-3.5 Turbo | $0.0005 | $0.0015 |
| GPT-4o Mini | $0.00015 | $0.0006 |
| GPT-4o | $0.005 | $0.015 |
| Claude 3.5 Sonnet | $0.003 | $0.015 |
| Claude 3 Haiku | $0.00025 | $0.00125 |
| DeepSeek V3 | $0.00014 | $0.00028 |
Getting Started in 5 Steps
Create an Account
Sign up with your email. Takes about 60 seconds, just email and password, no lengthy onboarding.
Add Funds
Deposit as little as $5. They take credit cards, crypto, and a few other options.
Get an API Key
Dashboard -> API keys -> generate. Copy it somewhere safe.
Pick a Model
Start with GPT-4o Mini if you're not sure. It's cheap and handles most things fine.
Start Sending Prompts
Use the web interface or connect via API. You only pay for what you use.
What most people actually spend
- Casual user (5-10 prompts/day): $3-5/month
- Moderate user (20-50 prompts/day): $8-15/month
- Heavy user (100+ prompts/day): $20-40/month