Token Estimator
Estimate token count from text length with an explicit heuristic and understand why tokenizers differ.
Fast, browser-based calculators for the technical decisions that show up in AI development: token budgets, LLM costs, model memory, and classification metrics.
Every result shows the formula, what is being estimated, and where the model breaks down.
ModelMetric Lab is a browser-based collection of transparent calculators and learning guides. It helps developers estimate token usage, plan LLM API costs, evaluate classification models, and size GPU memory. The tools run without an account and show the assumptions behind every estimate, so you can use the result as a starting point rather than treating it as an unexplained answer.
Do the math in your browser, then read the explanation below it. The goal is not just a number; it is a reusable mental model.
Estimate token count from text length with an explicit heuristic and understand why tokenizers differ.
Turn input/output token rates and request volume into per-request and monthly spend.
Convert a confusion matrix into precision, recall, F1, and accuracy.
Estimate weights memory from parameter count, precision, and an overhead factor.
These pages are intentionally longer than the tool UI: they target informational queries and teach the reasoning that makes the tool useful.
Why the answer is an estimate, how character count changes it, and how to budget prompts safely.
A transparent formula for input tokens, output tokens, request volume, and monthly spend.
A confusion-matrix-first explanation with examples and the trade-offs behind each metric.
Understand weight memory, precision, overhead, and why training needs more than raw model weights.
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View all guidesThe site is designed around calculations that can be shown, checked, and explained. For changing facts such as provider pricing, publish dated source notes and update the page instead of pretending a static number is forever correct.