Free tool · AI · no sign-up
Hashtag generator
Describe your post in a few words, pick the network, and get hashtags that fit the topic, with how many to use there and why each one was chosen.
A few words to a sentence, up to 200 characters. Free, no sign-up, about 10 a minute.
How to use it
- Describe the post, not your whole account. “Sourdough starter tips for beginners” gets better tags than “baking”.
- Pick the network you’re posting to. The number of tags and the style change with it: Instagram and TikTok get a mix of niche and broader tags, LinkedIn gets a few professional topics, X and Bluesky get one or two.
- Copy the best-fit set with one click, or click single tags to copy them one at a time. The line under each tag says why it was picked, so you can drop the ones that don’t match your post.
Read the tags before you post. They come from an AI model, and you know your audience better than it does.
Hashtags on each network
Instagram cut its limit from 30 hashtags to five per post in December 2025, so every tag has to earn its place. Pick the most specific ones and put them at the end of the caption, where they don’t get in the way of reading.
TikTok uses tags alongside the video itself to understand what a post is about. A few niche tags plus one broad one is a sensible mix.
X counts every tag toward the 280-character limit, and posts crowded with tags are harder to read. One or two is plenty.
LinkedIn posts usually end with two or three professional topic tags. Threads shows one topic tag per post, so choose the one that describes it best.
YouTube shows the first few hashtags from a description above the video title. Pinterest search leans on descriptive keywords, so plain, specific tags help more than trending ones. On Bluesky, tags become clickable feeds; one or two is enough. Facebook gives them little weight, so keep it to one or two.
What makes a good hashtag
- It describes this post, so someone who taps it finds what they expected.
- It is specific enough that your post isn’t lost among millions of others.
- It is easy to read: capitalise words in long tags (#SourdoughStarter).
- It isn’t misleading, and it isn’t a trending tag with nothing to do with you.
Questions
- How many hashtags should I use?
- Fewer than you think. Instagram now counts at most five hashtags on a post (it used to allow 30), and three to five specific tags read better anyway. On X every tag eats into the 280-character limit, so one or two is plenty. Threads shows one topic tag per post. The generator tells you the number it suggests for the network you picked.
- Are these the most popular hashtags?
- No, and that is on purpose. The tool doesn’t look up live tag volumes: it suggests tags that describe your topic, mixing specific ones with a few broader ones. The biggest tags are crowded, and a tag only helps if it matches what the post is about.
- Is it free? Do I need an account?
- Yes, it’s free and there’s no sign-up. To keep it that way there’s a limit of about 10 generations a minute per person and a daily cap across everyone. If you hit it, wait a minute and try again.
- What happens to what I type?
- Your topic goes to our tools server, which passes it to an AI model to write the suggestions and sends them back. The server doesn’t save it. Still, don’t paste anything private into it.
- Can I add hashtags to posts automatically?
- If you build software that posts to social networks, the postpeg API takes the post text, hashtags included, and publishes it to every network you choose in one request, after checking it fits each one’s limits.
More free tools
- Post idea generatorA week of post ideas with hooks and outlines, one per day.
- Character counterCheck one post against every network’s text limit at once.
- Best time to postCited posting windows per network, shown in your time zone.
- Image size guidePost, story, profile and cover sizes, and which ones your image fits.
- Text formatterBold, italic and monospace text you can paste anywhere.
For developers
Publish to all of them with one API call
postpeg is an API for products that post to social networks. Write the post once, and it is checked against every network’s rules, then published or scheduled on any mix of the 10 networks we support, with a status for each account.