Tools

Free AI Token Calculator

Estimate tokens, characters, words, and reading time from any prompt. Then compare approximate LLM costs across providers. Instant, free, and counted in your browser.

Type or paste text to calculate stats.

Privacy note: text is counted entirely in your browser — no prompt data is sent to ModelRiver. If you accept analytics cookies, anonymous usage statistics may be collected.

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

Estimated tokens use the common rule of thumb characters / 4, which approximates the token density of GPT-4, GPT-3.5, and Claude models for English text. Non-English text, code, and rare words may tokenize differently. For exact counts, use your provider's own tokenizer.

Cost examples use the same token estimate for both input and output and reflect standard on-demand per-million-token pricing synchronized with our model catalog on July 27, 2026. Actual costs depend on your provider's input/output rates, any volume discounts, and the real token count from the model's tokenizer.

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 the lowest-cost current model from the ModelRiver provider catalog, not a claim about the cheapest model worldwide. Cost examples assume the output contains the same estimated number of tokens as the input and reflect standard on-demand pricing — not reserved, batch, or committed-use discounts. Token counts remain approximate because model tokenizers differ. Prices are synchronized with our model catalog and may change.

Need to use these models in production? Explore ModelRiver to route requests, switch models, and track usage.

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.
Which models does this estimate approximate?
The characters-per-4 rule of thumb approximates token counts for GPT-4, GPT-3.5, and Claude models on English text. Non-English content, code, and rare or specialized words may produce different token counts. For production use, always verify with your provider's tokenizer.
Does my text leave the browser?
Text is counted entirely in your browser. The calculator does not send your prompt to ModelRiver. If you accept analytics cookies, anonymous usage statistics may be collected.

Use these models in production with ModelRiver

Route requests to 100+ models across 13 providers, switch models on the fly, track token usage in real time, and set per-workflow budget controls — all from one API.

Start free View pricing