How much does resending chat history cost?
Need to estimate the cost of resending chat history? Tokens are the unit AI providers bill in, and getting the count wrong throws off every cost estimate. This page helps teams tuning chat memory get an accurate count and the cost that follows from it.
Results update automatically as you type.
- Total input tokens (full history)
- 70,300 tokens
- Session cost — full history
- $0.0135
- Session cost — 6-turn window
- $0.00904
- Saved by windowing
- $0.00450
Why this isn't trivial
The part people underestimate: resent history is billed as input on every turn, so a long thread pays for the same early messages many times over. In practice the biggest savings come from windowing history or summarizing older turns, so it is worth modelling before you commit.
How it's calculated
We estimate this by summing the resent history tokens across turns at the model's input rate. Every figure uses the current provider prices baked into the site (reviewed daily), and you can override any input to match your own assumptions.
Frequently asked questions
Why is history so costly?+
You re-pay for the same messages every turn they remain in context.
Window or summarize?+
Windowing is simplest; summarizing preserves more context for the same cost.
Are these prices up to date?+
Yes. The model prices behind this calculator are refreshed and reviewed daily, so your estimate reflects current provider rates rather than a stale snapshot.
Related
Estimates for planning. Pricing data last reviewed 28 July 2026.