Understand rough token counts, context windows, and why exact tokenization varies by model.
AI models read text as tokens, not words. A rough English estimate is one token per four characters, but exact counts vary by tokenizer and language.
When planning a prompt, reserve room for the model’s response. A prompt that technically fits the full context window can still fail if no output budget remains.
Use the LLM Token Counter and Context Window Checker for quick browser-side estimates.
Estimate prompt tokens, characters, words, and rough model budget before sending text to an AI model. Runs in your browser with no account required.
AI ToolsCheck whether a prompt is likely to fit within a selected model context window. Runs in your browser with no account required.
AI ToolsEstimate AI API spend from input tokens, output tokens, and common model pricing presets. Runs in your browser with no account required.