Context Estimator Guide
Choose practical context windows for AI chats before you load a local model or paste a long document.
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1. Overview
Context Estimator gives you a fast estimate of how much AI chat context a piece of text or a document may need. It is useful before choosing settings such as 4K, 8K, 16K, 32K, 64K, or 128K in tools like Ollama, LM Studio, or local browser chat.
Estimate, not exact count: Different models tokenize text differently. The tool gives a practical planning estimate without downloading tokenizers.
2. Basic Workflow
Paste or upload
Paste text into the input area or choose a local TXT, DOCX, or PDF file.
Choose profile and reserve
Select the closest model profile and keep a reserve for system prompt, answer, formatting, and reasoning.
Read the comparison table
Use the row marked recommended as the minimum practical context window. If the fit is tight, choose the next larger window.
3. Model Profiles
Generic LLM
A safe default when you do not know which tokenizer your model uses.
Model families
Llama / Mistral, Qwen, Gemma, and GPT-style profiles adjust the estimate for common tokenization patterns.
4. Reserve
A context window must hold the source text, your instruction, system prompt, and generated answer. The reserve slider keeps part of the window free before making a recommendation.
The default 35% is a practical starting point. Increase it for detailed answers or reasoning. Lower it only when you expect a short answer.
5. Statuses
Too small / Tight
The input may overflow, or there may be little room left for a useful answer.
Good / Overkill
Good is the practical target. Overkill means the window is likely larger than needed.
6. Privacy and Limits
Text extraction and estimation run locally in your browser. Pasted text and uploaded files are not sent to ASD123.ai for processing, and document contents are not saved in localStorage or IndexedDB.
PDF extraction depends on readable embedded text. Scanned, image-only, password-protected, or unusual PDFs may need OCR or manual cleanup before estimation.