What is the Instagram algorithm?
"The Instagram algorithm" is a shorthand. In its 2023 guide, Instagram explained that each part of the app runs its own ranking system. Feed, Reels and Explore each look at what you have done before and predict what you will do next with each post.
That means there is no single score for a post. A Reel can rank well for strangers in the Reels tab and poorly for followers in Feed. To understand the Instagram algorithm, you have to look at each place separately.
This explainer sticks to what Instagram and Meta have said in public, with dates. It is part of our instagram engagement increase playbook, which turns these rules into a weekly routine.
What does each part of Instagram try to predict?
Instagram has described the main prediction for each surface. The table keeps the wording close to its own.
| Surface | What ranking tries to predict | Said when |
|---|---|---|
| Feed | Whether you will spend a few seconds on a post | 2023 ranking guide |
| Reels | Whether you will watch to the end, like it and reshare it | 2023 ranking guide |
| Explore | Likes, saves and shares are the most important actions | 2023 ranking guide |
| Whole app | Watch time, likes and sends matter most | Mosseri, January 2025 |
Notice that different actions lead in different places. Saves matter in Explore. Watching to the end matters in Reels. Sends show up in both the 2023 and the 2025 statements.
What do likes do on Instagram?
A like is the lightest action, but it is one of the three top signals Mosseri named in January 2025. He added that likes are "slightly more important for connected content", which means posts shown to people who already follow you.
So likes matter most with your current audience. A post your followers like a lot tells Instagram the account is still serving them well. Mosseri suggested tracking likes per reach in Insights instead of the raw count.
Here is the plain maths. A post with 150 likes from 3,000 viewers has 5 likes per 100 viewers. A post with 150 likes from 1,000 viewers has 15 per 100. Both show 150 likes, but the second post landed much better with the people who saw it.
What do shares and sends do?
Instagram counts two kinds of sharing. A send is when someone taps Share and sends your post to a person or group in a chat. A story reshare is when someone adds your post to their own story.
Sends are one of the three top signals, and Mosseri said they matter a bit more for people who do not follow you. That makes sends the main way a post reaches strangers. In August 2024, he also called views and sends per reach key metrics.
You cannot see who sent your post. Instagram's help pages say the poster is not told about chat sends, and you won't be able to see who reshared your Reel. You can see the total inside Interactions.
What do saves do?
A save is private. Instagram says only you can see the posts you've saved, and the poster cannot tell who saved. Saves still count: Instagram lists them inside Interactions, next to likes, comments and shares.
Explore is where saves carry the most weight in Instagram's public statements. The 2023 guide named likes, saves and shares as the most important actions there. Posts people want to keep, such as steps, lists, guides and recipes, are the ones that earn saves.
What do reposts do?
Reposts arrived on August 6, 2025, for public Reels and feed posts. Meta said reposts will be recommended to the reposter's friends' and followers' feeds, and they are credited to the original poster.
That gives reposts a clear job: they carry your post to the reposter's audience, including people who do not follow you. Creators can turn reposts off under Sharing and reuse, and nobody can repost a repost. Instagram has not said how much weight a repost carries in ranking, so treat it as a path to new viewers rather than a scored signal.
What do comments do?
Comments sit inside Interactions in Insights, next to likes, saves and shares. They were not among the three top signals Mosseri named in January 2025, and Instagram has not given them a separate weight in the sources this guide uses.
Comments still matter to people. A reply thread shows new viewers that the account is active and that someone answers. One detail is new: comments on a repost reach the reposter as direct messages, not as public comments under the post.
How do views fit in?
Since August 2024, Views is the main number across Reels, Stories, photos and carousels. Instagram defines a view as the number of times your content was played or displayed. For Reels, replays count too.
Views are not the same as Viewers. Viewers counts unique accounts. Instagram's Creators FAQ says what matters is "how much engagement per viewer the content has received", which is why per-viewer maths beats raw totals.
Which algorithm claims has Instagram never made?
Many popular tips have no official backing. These are the ones Instagram has not published in the sources this guide uses.
| Claim you will hear | What Instagram has said |
|---|---|
| There is an official engagement-rate formula | No official formula is published |
| There is one best hour to post | Post when your audience is awake and most active |
| There is an ideal Reel length | Only that Reels over 3 minutes are not recommended to new audiences |
| Hashtag counts set your reach | Not part of the named top signals |
| Instagram pays per view | No official per-view pay page found |
When an article states one of these as fact, look for a dated source. If there is none, treat it as opinion. Our guide to the best time to post on instagram shows how to test your own timing instead.
How do you check the signals in Insights?
Insights now work for any public account, personal or professional. Tap View insights under a post or Reel to see its numbers.
- Open the post and tap View insights.
- Note Views and Viewers.
- Open Interactions to see likes, comments, saves and shares.
- For Reels, note Average watch time next to the Reel's length.
- Divide likes and shares by Viewers, then multiply by 100, to get per-100 figures.
- Compare those figures with your last five posts.
Insights cover up to the past 90 days, so check monthly to keep a record. When you want to share a post for feedback, our guide on how to copy instagram post link text shows the steps.
What does the algorithm mean for bought engagement?
Instagram has acted against fake numbers in the past. On November 19, 2018, it said it would remove inauthentic likes, follows and comments from accounts that used third-party growth apps. Meta's spam policy bans selling, buying or exchanging engagement.
Rizula sells likes, views, shares, reposts and saves for one post per order, from $0.99 for 100 likes. It does not promise reach, ranking or a viral result. In the US, the FTC rule 16 CFR Part 465 bans buying or selling fake indicators of social media influence for a commercial purpose, so get legal advice before using bought numbers for business. Read the full rules in our likes guide section on whether buying Instagram likes is allowed, and see every option in the services section.
For a practical plan built on these signals, read our guide on how to go viral on instagram.