An AI cost calculator
Know what AI will cost you before the bill arrives.
For anyone paying for AI tools like ChatGPT: say how much you plan to use AI, and Promptmeter shows the price on every major AI model, picks the cheapest one that can do the job, and turns the total into SOL.
Model prices are list prices we recorded in mid-2025, and you can edit them. The SOL price is live. Nothing you type leaves this page.
Model · Claude Sonnet 4simulation
Service summary
How it works in 3 steps
- 01You give
How much you'll use AI, or a sample prompt.
- 02It works out
The price of that on every major AI model.
- 03You get
The cheapest model that fits and a monthly bill, in dollars and SOL.
Nothing is moved or charged. Promptmeter never sends a transaction; signing in with your wallet is optional, free, and moves nothing.
Schedule A
What every AI model charges
What this does: it prices the AI use you describe on every major model, cheapest first.
AI services bill per token, roughly ¾ of a word. Tell it how many requests a day and how long each is. Prices are editable: click any rate to change it, and your edits stay in this browser.
A customer-support chatbot answering 500 questions a day.
Reference rates: provider list prices in USD as we recorded them in mid-2025. They are not fetched live and prices change; check the provider before you commit.
Schedule B
Count what you'd be billed for
What this does: it counts the tokens in your text and shows what sending it once would cost.
Paste anything you'd send to an AI. The page cuts it into pieces the way ChatGPT-style models do and counts them. It is an estimate, and nothing leaves the page.
Fills a typical "write me an email" request.
- Estimated tokens
- 0
- Characters
- 0
- Words
- 0
- UTF-8 bytes
- 0
- Pre-tokens
- 0
- Chars / token
- 0
Estimate (model): real counts differ by tokenizer, typically within 10 to 15 percent for English prose, more for code and non-Latin text.
Schedule C
Find the cheapest model that can do the job
What this does: it picks the lowest-cost AI model that meets your needs, and says why the others lost.
Say how much text it must read at once (its context window), how smart it must be, and whether it must read pictures. The router prices your usage on each model that qualifies.
A top-quality model that reads photos and long documents.
Schedule D
Pay in SOL: how long would a wallet last?
What this does: it shows your monthly AI cost in SOL, and how many days a wallet's money would cover it.
SOL and USDC are the money people hold in Solana wallets. The SOL price is live from Jupiter. Connect your wallet, or paste any public wallet address, to see its runway. It only reads balances.
Reads a large public wallet. No wallet of yours needed.
- SOL balance
- –
- USDC balance
- –
- Wallet value (SOL + USDC)
- –
Read-only. Balances come from Solana mainnet through this site's RPC proxy.
Schedule E
Log in to AI services with your wallet
What this does: it shows how a wallet can replace an email and password when you sign up for an AI service.
The service shows you a one-time code, your wallet signs it, and the service checks the signature. Here you can play both sides in your browser. It never moves money.
Makes a throwaway test key, signs, and checks it. No wallet needed.
1Challenge
2Sign and derive
Your wallet signs the exact text on the left. Signing is free and moves nothing.
- Signer
- –
- Signature
- –
- Ed25519 check
- –
- Key fingerprint
- –
3Verify as the server
Statement
Your monthly AI bill
What this does: it adds up the AI costs you pick into one bill you can save as a spreadsheet.
Press Add on any price row, or add the router's pick. Totals show in dollars and in SOL at the live price. Saved only in this browser; download it as a CSV spreadsheet.
Adds the router's pick and makes the spreadsheet.
| # | Item | Quantity | Amount USD | Amount SOL | Remove |
|---|---|---|---|---|---|
| Total due | $0.00 | – |
How a reading is taken
One prompt, through the meter
- SplitThe text is cut into pre-tokens: words with their leading space, digit runs, punctuation.
- CountEach piece is sized into byte-pair tokens and the counter turns over.
- PriceInput and output tokens are multiplied by the model's rate per million.
- ConvertThe dollar amount is divided by the live SOL price from Jupiter.
- BillA line prints on your statement, signed by nobody but you.
Notes to the statement
How every number is made
Text cost
req × days × (in × (1 − c) × rate_in + in × c × rate_cached + out × rate_out) ÷ 1,000,000
c is your cached share. Models without a cached rate are charged the full input rate.
Image and video
units × days × rate_per_unit
Images are priced per standard 1024-pixel image, video per generated second.
SOL conversion
USD ÷ Jupiter price v3 (SOL)
Read every 30 seconds while the page is open. Nothing is swapped or charged.
Runway
(SOL × price + USDC) ÷ (monthly USD ÷ 30)
Uses the address's mainnet balances. It is arithmetic, not advice.
Key fingerprint
"pm_" + hex(SHA-256(signature))[0..24]
Deterministic for one challenge and one wallet; a server would store it as your key id.
Token estimate
Σ size(piece), piece from the GPT pre-tokenizer regex
A model of a tokenizer, not a tokenizer. The vocabulary files are megabytes; we chose not to ship them.
Questions
Frequently asked
What is this, in one sentence?
Promptmeter is a free calculator that shows what using AI models like ChatGPT, Claude or Gemini would cost you, which one is cheapest for your job, and what that is in SOL.
Is it safe? Does it touch my money?
It never touches your money. Promptmeter cannot send a transaction at all. Connecting a wallet only shares your public address so it can read your SOL and USDC balance. The optional "sign" button asks your wallet to approve a plain text message, which is free and moves nothing. It never asks for your secret recovery phrase. The prices are reference numbers, not a quote, so check the provider before you commit.
Are these prices live?
No. The rate card holds provider list prices as we recorded them in mid-2025, clearly labelled as reference rates. Providers change prices often, so every rate is editable. The only live market number on this site is the SOL price from Jupiter.
Does Promptmeter call any AI model?
No. It is a meter and a calculator. Nothing you type is sent to a model or to us; the counter, router and statement run in your browser.
Why sign a challenge with my wallet?
It shows how a service could give you an API identity without an email or KYC: your wallet proves it controls an address, and the service checks the Ed25519 signature. The site verifies it locally so you can see it work.
Can this site spend my SOL?
No. Connecting shares only your public key. Promptmeter never builds a transaction; it only reads balances and asks your wallet to sign plain text if you press Sign.
How accurate is the token count?
It is an estimate labelled as one. The text is split exactly the way GPT-style tokenizers pre-split, then each piece is sized from its length and character class. Expect a 10 to 15 percent spread on English.
Where is my statement stored?
In this browser's local storage only. Clear it with the button under the statement, or export it as CSV first.
Glossary
Words explained
What this does: it explains, in plain words, the technical terms on this page.
- Token
- A small piece of text, about ¾ of a word. AI services bill per million tokens, for text in and text out.
- Input / output
- Input is what you send the AI. Output is what it writes back. Output usually costs more.
- Repeated (cached) input
- Text the service has seen recently, like fixed instructions. Many services charge less for it.
- Context window
- How much text a model can read at once. 128k tokens is about a 250-page book.
- Tier
- Our rough grouping of models: small (fast, cheap), mid (general work), frontier (the smartest).
- SOL, USDC
- SOL is Solana's main coin; its price moves. USDC is a digital dollar meant to stay at $1.
- Wallet address
- Like a public account number. Anyone can see its balance; only the owner can move anything.
- Signature, signing
- Your wallet approves a piece of text so others can check it came from you. Free, moves nothing.
- Challenge
- A one-time message a service asks you to sign, so an old signature can't be reused.
- Ed25519
- The kind of maths Solana wallets use for signatures. Your browser checks it with built-in tools.
- Runway
- How many days a pot of money would last at a given spending rate.
- Mainnet
- The real, live Solana network (not a test copy).