---
title: "Spaced repetition: What the Research Says"
description: "Plain-language summaries of studies on spaced repetition: methods, findings, effect sizes and limitations."
canonical: https://research.askpoppy.ai/topics/spaced-repetition/
last_updated: 2026-10-21
---

# Spaced repetition: research in plain words

Spreading study over days beats cramming the same amount into one sitting. The question is how far apart.

## Summaries (1)

### [Spacing beats cramming: the classic review of 317 experiments](/papers/cepeda-2006-distributed-practice-meta-analysis/)

Nicholas J. Cepeda et al. (2006) · Review and meta-analysis (landmark classic) · Peer-reviewed

Across 839 assessments in 317 experiments, spreading study over separate sessions beat doing it all at once, and in only 12 of 271 direct comparisons did spacing show no benefit or a cost. The best gap between sessions grows with how long you need to remember the material.

## Free tools for this

- [Exam countdown and spaced revision plan](https://learn.askpoppy.ai/countdown/)
- [Active recall flashcards with spaced review](https://learn.askpoppy.ai/recall/)
- [7-day learn-out-loud challenge](https://learn.askpoppy.ai/learn-out-loud/)

Each summary says what the researchers did, who took part, what they found, the limitations, and whether we read the full paper or only the abstract.

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