Tools

AI Token Calculator

Estimate AI token usage in real time. Paste your prompt below and see character, word, line, paragraph, reading time, and token estimates instantly.

Type or paste text to calculate stats.

Privacy note: everything is calculated locally in your browser. No API calls, no data storage.

Characters
0
Words
0
Lines
0
Paragraphs
0
Estimated Tokens
0
Reading Time
0s

Estimated tokens use the common rule of thumb characters / 4. Every provider and model uses its own tokenizer, so actual counts vary. The cost comparison applies the same token estimate to standard on-demand per-million-token pricing synchronized with our model catalog on July 15, 2026.

Lowest-cost current model by provider

Compare the lowest-cost current model from each provider using your estimated token count.

Open AI Pricing Calculator (opens in a new tab)

Each selection is a current low-cost model from the ModelRiver provider catalog. Cost examples assume the output contains the same estimated number of tokens as the input. Token counts remain approximate because model tokenizers differ.

What are AI tokens?

Large Language Models (LLMs) do not read words the way humans do. Instead, they process text as tokens, which can be entire words, fragments of words, or individual characters. A tokenizer trained on a specific model decides how every input is split.

For example, the word "tokenization" might be split into "token" and "ization" for some models, while others keep it whole. This is why the same prompt can cost a different number of tokens depending on the model.

Browse ModelRiver's model catalog to compare token rates across providers, or learn how ModelRiver tracks usage in analytics.

Why token counts matter

Cost control

Providers bill by input and output tokens. Knowing the size of a prompt helps you estimate the cost before you send a request.

Context limits

Every model has a maximum context window measured in tokens. Large prompts leave less room for the model's response and instructions.

Latency

Longer inputs usually take more time to process. A quick token estimate helps you decide whether to trim context.

Budget guardrails

Set spending limits on workflows and models so that unexpected token usage never surprises your bill. See AI spending limits.

Frequently asked questions

What are AI tokens?
AI tokens are the small pieces of text that Large Language Models use to read and generate language. A token can be a word, a fragment of a word, or a single character, depending on the model's tokenizer.
How does this token calculator estimate tokens?
This calculator estimates tokens by dividing the character count by 4 and rounding up. This is a common rule of thumb for English text and matches the approximate token density of many GPT and Claude tokenizers.
Why do token counts matter?
Token counts determine the cost, speed, and context limits of LLM requests. Providers charge per token, context windows are measured in tokens, and longer prompts usually mean slower responses and higher bills.
Is the estimate exact?
No, the estimate is approximate. Different models and tokenizer versions split text differently. Use this tool for quick planning and your provider's own tokenizer for exact counts.
Does my text leave the browser?
No. All counting happens locally in your browser. No API calls are made and no text is sent to a server or stored anywhere.

Ship AI features with ModelRiver

One API for every AI model. Route requests, switch models, track tokens, and guard your budget from a single platform.

Start free View pricing