Context Window Packer

Fit as many RAG chunks as possible into a model context budget.

Works Offline
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No Login
No API
Packed tokens
1,112 / 128,000
Chunks included
3 / 3
Context space left
126,888
Tokenizer
Estimating…

Chunks (separated by your delimiter)

Packed context

About the Context Window Packer

Split your retrieved chunks by a delimiter, set the system prompt, question and reply reservation, then let the packer greedily fill the remaining context window. It numbers the included chunks, shows exactly which ones were dropped and exports the final prompt ready to send.

Examples

3 chunks

3 retrieved passages + question

Output

All 3 packed — 231 / 128,000 tokens

Keyboard shortcuts

  • Copy the main outputCtrl / ⌘ + Shift + C
  • Download the resultCtrl / ⌘ + S
  • Share this toolCtrl / ⌘ + Shift + S
  • Reset the inputsAlt + R
  • Open the tool search paletteCtrl / ⌘ + K

Related tools

Frequently asked questions

Version 1.0.0 · Updated 2026-08-15 · Runs entirely in your browser