---
title: 'How do I change the TPO block size and sessions?'
description: 'In the TPO settings, General sets the Block Size (5m, 30m, 1h or 4h), the Session Type (daily, weekly or monthly) and the Trading Hour window, or custom sessions.'
category: indicators
kind: faq
keywords:
  [
    tpo,
    market profile,
    block size,
    tpo period,
    15 minute,
    30 minute,
    session,
    trading hours,
    custom sessions,
    profile width,
  ]
updatedAt: '2026-10-20'
popularity: 5
---

# How do I change the TPO block size and sessions?

Hover the TPO row in the chart legend and click the gear. The **General** tab holds what traders change most:

- **Block Size**: how much time one TPO block (one letter) covers: 5m, 30m, 1h or 4h. 30m is the default; 15-minute blocks are not an option.
- **Session Type**: one profile per day, week or month.
- **Trading Hour**: limits each daily profile to a session window, such as Regular (09:30 to 16:00 ET), London or New York, or **Custom** with your own start and end times. That is how you set where a trading day starts and ends.
- **Custom sessions**: splits each day into up to 8 colored session profiles.
- **Ticks per bar** sets the height of each price row, and **Profile spacing** adds a gap between neighboring profiles.

Every option is documented tab by tab in the [TPO settings reference](/learn/order-flow/tpo/settings-reference).