> ## Documentation Index
> Fetch the complete documentation index at: https://promostar.app/help/llms.txt
> Use this file to discover all available pages before exploring further.

# How to use PromoStar to find the best time to post in a subreddit

> Prime Time shows a weekday-by-hour heatmap of when strong posts land in each subreddit, so you can find the best time to post on Reddit.

Open **Prime Time** in the sidebar, pick a subreddit, and read its weekday-by-hour heatmap to see when strong posts tend to land there.

## Steps

1. Click **Prime Time** in the sidebar. The page opens with no subreddit selected.
2. Click the **Subreddit** box and type at least two letters of a name, with or without `r/`. Subs you starred appear first under **Your subs**. Other matches appear under **From the pool**.
3. Pick a sub. Its heatmap loads, with days down the side from Monday and hours across the top. Darker violet means a higher median score for posts created in that hour.
4. Hover over a cell, or tab to it, to see the median points, the number of posts, and the best hot rank when there is one.
5. Check **Peak windows** above the grid for up to three of the strongest weekday and hour slots.
6. Click **Plan a post** to open the composer with this sub already chosen.

<Info>
  Prime Time only sees posts that already did well enough to reach the sub's hot or top listings. It shows when strong posts tend to land, not how likely your post is to succeed.
</Info>

## Good to know

* Times use the zone set under **Settings** > **Preferences** > **Timezone**. **Auto** follows the device you are on. The line above the grid shows the zone in use.
* Shading compares hours within one sub only. A dark cell in a small sub is not comparable to a dark cell in a large one.
* Faded cells with a dashed border rest on one or two posts, so treat them as uncertain. Grey cells have no data. **Peak windows** only count slots with at least three posts.
* The picker lists only tracked subs that already have data. A sub that is missing is either not tracked or has no reads yet. A new sub needs a couple of weeks of reads before its heatmap means much.
* Click the star next to the picker to pin the selected sub under **Your subs**.

## Where the data comes from

The Prime Time collector runs on PromoStar's own server. It reads the public hot and top listings of each tracked subreddit and stores the post times and scores in PromoStar's database. It does not use your Reddit account and does not read your media.


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