Before you set a price · Stage 2: check demand
How to price an app that calls an LLM, using current model list prices
On the 13 list prices in our table, one AI action costs you from $0.00034 to $0.05. Here is the arithmetic on prices checked 2026-10-13, the plan that survives a heavy user, and the limits that stop free users spending your API budget.
Updated
Key takeaways
- At list prices as of October 2026, one action of 2,000 input and 600 output tokens costs $0.0005 on Haiku 5.5 or gpt-6-luna, $0.01 on Sonnet 5.5 or gpt-6.1-sol, and $0.05 on Fable 5.1 or gpt-6-astra. Same call, 100 times the price.
- At list prices as of October 2026, a $9 monthly plan pays for 900 Sonnet 5.5 actions before payment fees. A user who runs 50 a day (our assumption) costs you $15.00 a month on Sonnet 5.5 and $0.75 on Haiku 5.5.
- Two list prices have dates attached: Gemini 3.8 Flash doubles on 2027-01-01, and the promotional price for GPT-5.6 Sol runs at least through 2026-11-21, per OpenAI.
- Stripe's guide says to pick a unit that gives customers more value as it grows, check that your costs rise with it, and run the math on your worst-case customer. Vellum reported 28% more total revenue after sending out-of-credit free users to Upgrade instead of Add Credits (one company's own test).
- Put sign-in in front of every call that costs money, cap actions per user, and set a hard spend limit at the provider. OpenAI and Anthropic both let you set your own monthly API spend limit.
Price it in five steps
Do these in order, with your real prompt and a calculator. Steps 1 and 2 are arithmetic. Steps 3 to 5 are our call (editorial) for a solo builder shipping a first paid app with Cursor, Claude Code, Lovable, Bolt, v0 or Replit.
Step 1: Work out the cost of one action
An action is one thing the user sees: a summary, a draft, a reply. If it takes three model calls (plan, draft, check), add all three. Cost of one action = (input tokens × input price + output tokens × output price) / 1,000,000, with prices per 1M tokens. On Sonnet 5.5 at list price as of October 2026: (2,000 × $2 + 600 × $10) / 1,000,000 = $0.004 + $0.006 = $0.01. If one action takes three Sonnet 5.5 calls of this size, it costs $0.03, and a $9 plan covers 300 actions. Take token counts from your own API responses (the usage fields, such as input_tokens), not from estimates. Google bills Gemini's thinking tokens as output, so a model that reasons before answering costs more than its visible answer suggests.[1], [3], [7]
Step 2: Run the heavy-user test
Multiply the cost of one action by what your heaviest plausible user does in a month. Our assumption on this page is 50 actions a day, about 1,500 a month. On Haiku 5.5 that user costs $0.75. On Sonnet 5.5 they cost $15.00, more than a $9 plan brings in. Stripe's guide gives the same advice: find the usage pattern that makes a customer unprofitable, then add caps, overage fees or tier limits. Builders on r/SaaS ask this about flat-priced AI agents, and a 2026 r/microsaas thread describes spotting money-losing users only when the invoice arrived. Track cost per customer as well as the total bill.[1], [4], [10], [9]
Step 3: Price in a unit customers understand
Buyers count documents, reports, replies or projects. Sell a plan with an included amount of that unit, meter tokens on your side, and sell credits as top-ups for people who go past it. Vellum puts it as "Price in the unit your customer understands." In its own test from July 23 to August 17, 2026, free users who ran out of credits saw Upgrade instead of Add Credits: credit purchases fell 44% and total revenue rose 28% over about three and a half weeks. That is one company reporting on itself, with no sample size given. Vellum sells an always-on assistant, so the result says most about products people use every day. Run your own version before you rely on it.[5]
Step 4: Subtract payment fees
Stripe and Paddle each charge a percentage plus a fixed amount per transaction, so the fixed part takes a bigger share of a small plan. The fee comparison for Stripe, Paddle and Lemon Squeezy lives on the costs page. For a whole monthly bill at 500 users, with hosting, database and email, see scenario B.[13], [14]
Step 5: Protect the free tier before launch
Every free action is one you pay for. OWASP's entry on unbounded consumption (LLM10) names the attack "Denial of Wallet": someone runs up your pay-per-use bill on purpose. A 2026 r/SaaS thread describes fake signups burning through free credits. The checklist below lists the controls to set first.[8], [12]
Cost of one action by model
One action = 2,000 input tokens + 600 output tokens, our default assumption on these pages. Standard list prices per 1M tokens as of October 2026, with no caching and no batch discount. The last two columns are our arithmetic.
| Model | Vendor | Input, per 1M tokens | Output, per 1M tokens | One action | 1,000 actions |
|---|---|---|---|---|---|
| gpt-5-nano | OpenAI | $0.05 | $0.40 | $0.00034 | $0.34 |
| Gemini 2.5 Flash-Lite | $0.10 | $0.40 | $0.00044 | $0.44 | |
| Haiku 5.5 (prompts up to 100K tokens) | Anthropic | $0.10 | $0.50 | $0.0005 | $0.50 |
| gpt-6-luna | OpenAI | $0.10 | $0.50 | $0.0005 | $0.50 |
| Gemini 3.1 Flash-Lite | $0.25 | $1.50 | $0.0014 | $1.40 | |
| gpt-5-mini | OpenAI | $0.25 | $2.00 | $0.0017 | $1.70 |
| Gemini 3.8 Flash, through 2026-12-31 | $0.75 | $3.75 | $0.00375 | $3.75 | |
| Gemini 3.8 Flash, from 2027-01-01 | $1.50 | $7.50 | $0.0075 | $7.50 | |
| Sonnet 5.5 | Anthropic | $2.00 | $10.00 | $0.01 | $10.00 |
| gpt-6.1-sol | OpenAI | $2.00 | $10.00 | $0.01 | $10.00 |
| Opus 5.5 | Anthropic | $4.00 | $20.00 | $0.02 | $20.00 |
| Fable 5.1 | Anthropic | $10.00 | $50.00 | $0.05 | $50.00 |
| gpt-6-astra | OpenAI | $10.00 | $50.00 | $0.05 | $50.00 |
Prices checked on vendor pages 2026-10-13. OpenAI prices are for short context (up to 272K input tokens). Gemini output prices include thinking tokens. The same vendor pages list models that cost more than any row here: gpt-5-pro is $15.00 input and $120.00 output per 1M tokens, or $0.102 an action. Model names are as each vendor prints them; line-ups change often.[1], [2], [3]
What a $9 plan covers
Derived from the table above. $9 a month is an example price, before payment fees, hosting and retries. The heavy user is our assumption: 50 actions a day, 1,500 a month.
| Model | One action | Actions $9 pays for | Heavy user, per month | What is left of $9 |
|---|---|---|---|---|
| gpt-5-nano | $0.00034 | about 26,470 | $0.51 | $8.49 left |
| Gemini 2.5 Flash-Lite | $0.00044 | about 20,450 | $0.66 | $8.34 left |
| Haiku 5.5 or gpt-6-luna | $0.0005 | 18,000 | $0.75 | $8.25 left |
| Gemini 3.1 Flash-Lite | $0.0014 | about 6,430 | $2.10 | $6.90 left |
| gpt-5-mini | $0.0017 | about 5,290 | $2.55 | $6.45 left |
| Gemini 3.8 Flash, list price through 2026-12-31 | $0.00375 | 2,400 | $5.63 | $3.37 left |
| Gemini 3.8 Flash, list price from 2027-01-01 | $0.0075 | 1,200 | $11.25 | loses $2.25 |
| Sonnet 5.5 or gpt-6.1-sol | $0.01 | 900 | $15.00 | loses $6.00 |
| Opus 5.5 | $0.02 | 450 | $30.00 | loses $21.00 |
| Fable 5.1 or gpt-6-astra | $0.05 | 180 | $75.00 | loses $66.00 |
Prices checked on vendor pages 2026-10-13. Counts are rounded to the nearest 10 where the division is not exact.[1], [2], [3]
Four ways to lower the cost of one action
Same action as the tables: 2,000 tokens in, 600 out, list prices as of October 2026.
- Cache the repeated part of the prompt. If 1,500 of the 2,000 input tokens are the same system prompt on every call, Sonnet 5.5 reads them from cache at $0.10 per 1M tokens instead of $2.00. One action drops from $0.01 to $0.00715, before cache-write charges, which depend on your traffic. Replies in a 2026 r/SaaS thread on API costs rising with real use recommend caching and usage limits.[1], [15]
- Shorten the answer. Output costs 5 times as much as input on Sonnet 5.5. Cutting the answer from 600 to 300 tokens takes the same action to $0.007. Shorter answers and caching stack.[1]
Pricing models and when each fits
Stripe's guide covers flat or tiered, usage-based, hybrid, seat-based and outcome-based pricing. This table splits flat and tiered into two rows, keeps usage-based and hybrid, leaves out seat-based and outcome-based, and adds one-time purchase or license. The "fits when" and "watch out for" columns are our call (editorial).
| Model | How it charges | Fits when | Watch out for |
|---|---|---|---|
| Flat subscription | One monthly price, with a fair-use cap | The action runs on a small model. On Haiku 5.5 a 1,500-action month costs $0.75. | Stripe's guide warns that flat pricing puts margins at risk when power users drive up costs. |
| Tiers with included actions | Two or three plans, each with a set number of actions | Users differ a lot in how much they use the app | Too many tiers at launch. Stripe suggests starting with two, with usage charges in the upper one. |
| Usage-based or credits | Pay per action, or buy a pack of credits | Use is rare or spiky, and buyers already think in units: one-off reports, developer tools. Vellum names transactional products and developer infrastructure as fits. | Buyers who want a predictable bill. An r/SaaS thread sums up the tension: users want unlimited, founders want credits. |
| Hybrid | A plan with included actions, plus credit top-ups or overage | Most apps on a mid-tier model | Surprise bills. Stripe's guide says caps, alerts and credits that make use visible before it becomes a bill matter for any usage-based model. Show usage in the app and warn before a top-up or overage charge (editorial). |
| One-time purchase or license | Pay once | The app makes no paid model call, or each user brings their own API key | Model costs that keep running after the sale. A $9 one-time sale pays for 900 Sonnet 5.5 actions over the whole life of that customer. |
Prices checked on vendor pages 2026-10-13. Stripe guide last updated 2026-04-19; Vellum post dated 2026-09-02.[4], [5], [11], [1]
Before anyone can trigger a paid call
Tick each one before you open a free tier. Limits are as of October 2026.
- Sign-in before the first paid call. Anonymous visitors should never trigger a model call. Put the sign-in screen in front of the first action that costs you money (editorial).
- A daily cap per user. Set it from a budget. $30 a month for all free users buys 60,000 Haiku 5.5 actions: 10 a day for 200 active free users over a 30-day month. On Sonnet 5.5 the same $30 buys 3,000 actions: 10 a day for 10 users (our arithmetic, list prices as of October 2026).[1]
- A cap on input length. Long pasted documents raise the input side of every call. OWASP lists input size limits first among its mitigations for unbounded consumption. Rate limits, user quotas, timeouts and monitoring are on the same list.[8]
- A hard limit at OpenAI. Set a monthly spend limit on the project or the organization and turn on "Enforce a hard limit". Requests then fail with a 429 error once the limit is reached. OpenAI says enforcement is not instant, so spend can go slightly over, and that alerts on their own do not stop requests.[6]
- Your own limit at Anthropic. The Start, Build and Scale usage tiers each carry a monthly spend cap (Start: $500). Set your own lower limit under Settings > Billing in the Claude Console. Once it is reached, requests fail until access resumes or you raise the limit. Workspaces can carry lower limits than the organization.[7]
- No customer data on Gemini's free tier. Google's pricing page says free-tier content is used to improve its products and paid-tier content is not. Move to the paid tier before real users send real data.[3]
- Cost logged per customer. Store the token counts of each call against the user who made it, so you can see who costs more than they pay before the invoice does.[9]
Each Sonnet 5.5 action costs you $0.01. Check who would pay before you build.
Describe the app and who it is for, and Olune scores the idea free on seven dimensions, including willingness to pay. A free sign-in then runs the research: search demand, public complaints in Reddit threads found through Google, and competitors. You get Cook it, Sleep on it or Kill it, with the reasoning. 3 a day, no card.
Check what buyers already pay before you build
Your model cost sets the lowest price you can charge. What buyers pay today for the nearest alternative sets the highest price they will accept (editorial). If your heaviest user costs more than the alternatives charge, you can see that before you write any code.
Before you build, open the pricing pages of three tools your buyer could use instead and write down two things for each: the price and the unit (per seat, per document, per credit, per month). Then check one per-user cost from the tables above against the cheapest credible option. If the alternative is free and good enough, a paid AI version needs a reason to exist. How to validate willingness to pay covers pre-sales and deposits, which say more than a survey.
Olune covers part of this check. Before any research runs, it scores your description from 1 to 5 on seven dimensions. One is willingness to pay, where a 4 means the model judges that buyers already pay for competitors or adjacent tools. That score is a judgement from your text, not a measurement. After a free sign-in, the research looks at search demand, public complaints in Reddit threads found through Google, and 3 to 6 competitors. The competitor step is told to record a price only when the search result mentions one, so many rows show none.
The verdict is Cook it, Sleep on it or Kill it, with the reasoning. Kill is a normal result: a killed idea gets no Build Kit and comes with pivots instead, which can include a change of pricing. The analysis is LLM-assisted and can vary between runs. Olune does not compute token costs, margins or a price for you; that is what the tables on this page are for. See what Olune checks and what it cannot.
Run your idea with the price you have in mind
Write what the app does, who pays, what they use today and the price you plan to charge. Olune scores it free, and a free sign-in runs the research on demand, complaints and competitors. Kill is a normal result and comes with pivots. The analysis is LLM-assisted and can vary between runs. 3 a day, no card.
Common questions
How much should I charge for my AI app?
Charge close to what buyers already pay for the nearest alternative, then check that the price covers your heaviest user's model cost with room left for payment fees. On a $9 plan that check passes on small models such as Haiku 5.5 ($0.75 for a 1,500-action month at list price as of October 2026) and fails on Sonnet 5.5 ($15.00). If it fails, use a smaller model, cap usage or raise the price. This is our rule of thumb (editorial).
Should my AI app use credits or a subscription?
For most apps, a subscription with an included amount of use, plus credits as top-ups, is the simpler offer for buyers (our call, editorial). Stripe's guide suggests starting with two tiers, with usage charges in the upper one, and caps or alerts so no bill comes as a surprise. Vellum reported more total revenue when out-of-credit free users were sent to plans instead of a credit top-up, in one test of its own. Pure credits fit rare or spiky use, such as one-off reports.
How do I stop free users burning my API budget?
Require sign-in before any call that costs money, cap actions per user per day, cap input length, and set a hard spend limit with the model provider. On OpenAI, turn on "Enforce a hard limit" for the project, and requests return a 429 error once the limit is reached. On Anthropic, set your own limit below your tier's cap under Settings > Billing (the Start tier cap is $500 a month as of October 2026). OWASP covers these controls in LLM10, its entry on unbounded consumption.
What does one AI API call cost?
Across the models in our table, one call of 2,000 input and 600 output tokens costs from $0.00034 on gpt-5-nano to $0.05 on Fable 5.1 or gpt-6-astra, at standard list prices as of October 2026; some models on the same vendor pages cost more. The formula is (input tokens × input price + output tokens × output price) / 1,000,000, with prices per 1M tokens. Output costs 4 to 8 times as much as input on every model in the table above, so long answers drive the bill.
How do I work out LLM API cost per user?
Multiply the cost of one action by the number of actions that user makes in a month. The heavy-user column in the $9 plan table does this for 1,500 actions a month. Log token counts per user id from day one, so a user who costs more than they pay shows up in your own data before the provider invoice.
Can I use a free LLM API tier for a launched app?
Not with customer data on Gemini's free tier, and Anthropic's pricing page lists no free API tier at all. Google's pricing page says free-tier content is used to improve its products and paid-tier content is not. OpenAI's free-tier terms and every free tier's rate limits were not checked for this page.
Does Olune work out my token costs or margins?
No. Olune scores your idea on seven dimensions, one of which is willingness to pay, and after a free sign-in it researches search demand, public complaints and competitors. It does not compute token costs, margins or a price; use the tables on this page for that.
Sources
Each number in brackets on this page points here. Prices and limits change; the date is when we read the page.
- [1]Anthropic, Claude pricing (API model prices, batch discount) · accessed
- [2]OpenAI, API pricing (Standard, Batch; GPT-5.6 Sol promotional note) · accessed
- [3]Google, Gemini Developer API pricing (last updated 2026-10-09) · accessed
- [4]Stripe, AI SaaS pricing models: a guide for founders (updated 2026-04-19) · accessed
- [5]Vellum, Why subscriptions beat credits for AI products (2026-09-02) · accessed
- [6]OpenAI, API spend limits guide · accessed
- [7]Anthropic, Claude API rate limits and spend limits · accessed
- [8]OWASP GenAI, LLM10:2025 Unbounded Consumption · accessed
- [9]r/microsaas thread: flat AI pricing hides which customers lose money (2026) · accessed
- [10]r/SaaS thread: pricing AI agents without going bankrupt (2026) · accessed
- [11]r/SaaS thread: AI users want unlimited, AI founders want credits (2026) · accessed
- [12]r/SaaS thread: free tier abuse from fake signups (2026) · accessed
- [13]Stripe, pricing (US standard card fees) · accessed
- [14]Paddle, pricing (pay-as-you-go fee) · accessed
- [15]r/SaaS thread: AI API costs once people start using your app (2026) · accessed
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