Free Tool

LLM Context Window Checker

Paste your text and see which models can fit it — and which ones can't. Know your limits before you hit them.

Sets the output reservation automatically
0 chars · ~0 tokens
Tokens subtracted from context window to leave room for the model's response.
Token counts are estimated (~4 chars per token for English). Context windows shown are for the standard model variant — extended or cached variants may differ.
Context window status

Paste your text and click Check.

Green = fits · Yellow = close · Red = too long.

More free tools

Token Cost Calculator

Estimate API costs across all major LLM providers.

AI ROI Calculator

Calculate time and money saved by adopting AI tools.

Prompt Generator

Build structured, production-ready prompts in seconds.