Context Window

Opening — Why this matters now Long-context models have become the quiet arms race of the LLM ecosystem. Every few months, someone announces another context window milestone—128k, 1M, or “effectively unlimited.” The implication is obvious and seductive: if a model can read everything, it must understand everything. The paper behind this article is less impressed. It asks a colder question: what actually happens inside a model as context grows, and whether more tokens translate into more usable intelligence—or just more noise politely attended to. ...

Gemini 2.5 and the Rise of the 2 Million Token Era In March 2025, Google introduced Gemini 2.5 Pro with a 2 million token context window, marking a major milestone in the capabilities of language models. While this remains an experimental and high-cost frontier, it opens the door to new possibilities. To put this in perspective (approximate values, depending on tokenizer): 📖 The entire King James Bible: ~785,000 tokens 🎭 All of Shakespeare’s plays: ~900,000 tokens 📚 A full college textbook: ~500,000–800,000 tokens This means Gemini 2.5 could, in theory, process multiple entire books or large document repositories in one go—though with substantial compute and memory costs that make practical deployment currently limited. ...