AI API cost calculator
AI API cost calculator for monthly LLM spend
Compare OpenAI, Anthropic, Google & more — before the invoice
Estimate monthly LLM API spend across providers. Set tokens or requests, add models, and get a live USD breakdown you can share.
Model prices last updated 2026-09-08. Figures are estimates from approximate public list prices.
Scenario
Resolved volume: 10,000,000 in / 2,000,000 out per month
Models (2/3)
Live estimate
Prices last updated 2026-09-08. Estimates only.
Monthly
$62.70
Daily ≈
$2.09
GPT-4o mini
OpenAI
$2.70
in $1.50 · out $1.20 · $0.09/day
Claude Sonnet 4
Anthropic
$60.00
in $30.00 · out $30.00 · $2.00/day
Approximate public list prices for estimation only. Verify against provider docs before budgeting.
FAQ — AI API cost calculator
- How does the AI API cost estimate work?
- Pick one or more catalog models, enter monthly input/output tokens (or requests × average tokens), and TokenTally multiplies volume by each model’s approximate public list price per 1M tokens. You get a live monthly and daily USD estimate with a per-model breakdown.
- What is Free vs Pro? (3 vs 10 models)
- Free lets you compare up to 3 models in one scenario with a full line-item breakdown. Pro raises the cap to 10 models and unlocks CSV export. Prices stay as listed on the pricing page.
- Are these prices invoices or guarantees?
- No. Figures are estimates from approximate public list rates in our catalog. Providers change pricing, add discounts, and bill differently — always verify against official docs before budgeting.
- Which providers are included?
- The calculator ships with popular models from OpenAI, Anthropic, Google, DeepSeek, and others in data/models.json. Prices are snapshotted; the catalog shows the last-updated date.
- Can I share an estimate?
- Yes. Use Share estimate to create a public page with your models, volumes, and USD totals. Shares may be noindex when they are empty, duplicates, or over the daily public indexable cap.
How much does your AI stack cost?
Whether you're building a chatbot, a content generation pipeline, or a RAG system, LLM API costs are the single biggest variable expense. TokenTally helps you estimate monthly spend before you commit to a provider.
What affects your LLM API bill?
- Input vs output tokens — Output tokens typically cost 3-5× more than input. A chatbot that generates long responses costs significantly more than one that gives short answers.
- Model tier — Flagship models (GPT-4o, Claude Opus) cost 10-30× more than mini/lite versions. Many workloads don't need the flagship — use the calculator to see if a cheaper model fits your budget.
- Context window usage — Long prompts burn input tokens on every call. Trimming context by 50% can halve your input costs.
- Caching — Providers offer prompt caching that can reduce repeated input costs by 50-90%.
FAQ
How do I calculate my monthly token usage?
Estimate: (avg input tokens + avg output tokens) × requests/day × 30. Log your first 100 real requests to calibrate.
Which provider is cheapest for high-volume chatbots?
For 2026: DeepSeek V3 is typically 5-10× cheaper than GPT-4o-mini. Gemini Flash is also aggressively priced. Use the calculator above to compare your specific workload.
Should I use batch APIs to save costs?
Batch APIs offer 50% discounts for non-real-time workloads. If you're processing documents overnight, batch is the easiest cost cut.
How much should I budget for a side project?
A typical AI side project (100-1000 requests/day) on budget models costs $5-50/month. Production apps run $200-2000/month. Start cheap, upgrade only when quality demands it.