# Chunking Strategies Cheat Sheet
_How you split documents decides what retrieval can ever find_
Retrieval quality is capped by chunking. A fact split across two chunks is a fact your system cannot retrieve, no matter how good the embedding model is.
> Difficulty: advanced  
> Version: 1.0  
> Updated: 2026-08-05  
> Categories: RAG  
> Tags: Context Window, Embeddings, Vector Db

Source: https://invitationbuddy.com/cheat-sheet/chunking-strategies-cheat-sheet

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## Strategies
| Strategy | Splits on | Best for |
| --- | --- | --- |
| Fixed size | A token count  Uniform prose where structure does not matter |
| Recursive | Paragraph, then sentence, then word  The sensible default for mixed documents |
| Structural | Headings, sections, list items  Manuals, docs, anything with a real outline |
| Semantic | Embedding distance between sentences  Dense text with no markup; slow to build |
| Row / record | One record per chunk  Tables, CSVs, product catalogues |
| Parent-child | Small chunks that resolve to a bigger parent  When you must match precisely but answer with context |

## Sizing
| Content | Chunk | Overlap |
| --- | --- | --- |
| `FAQ / short answers` | 150–300 tokens  0–20 |
| `Documentation` | 400–800 tokens  50–100 |
| `Long-form prose` | 600–1000 tokens  100–150 |
| `Code` | One function or class  Repeat the signature and imports |
| `Tables` | One row, header repeated  0 |

## Metadata to store with every chunk
- [ ] Source document id and a stable URL — Without it you cannot cite, and an uncitable answer is unverifiable
- [ ] Heading path — the breadcrumb the chunk sat under — Restores the context you cut away
- [ ] Position in the document — Lets you re-expand to neighbours at answer time
- [ ] Last-modified date — The only way to prefer fresh content or expire stale content
- [ ] Access scope — Filter BEFORE the vector search, never after

## FAQs
**What chunk size should I start with?**
Recursive splitting at 400–800 tokens with 50–100 of overlap handles most documents. Then measure recall on real questions — the right size is a property of your content, not a constant.

**Is more overlap always safer?**
No. Overlap costs storage and returns near-duplicate chunks that crowd out genuinely different results. Use enough to keep a sentence from being cut in half, not more.

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_Generated from https://invitationbuddy.com/cheat-sheet/chunking-strategies-cheat-sheet_