How to Monitor Reddit for Keywords (Free and Paid)
September 21, 2026 · Threadly Blog
To monitor Reddit for keywords, pick the words you want to track, then use a tool that notifies you when a post or comment contains them. The options run from a free Google Alert to tools that read each post and score whether the author wants to buy. This guide compares five, with the costs and trade-offs of each, so you can set up the one that fits your budget and volume.
What monitoring is, and why keyword lists fail
Every method below does the same first step: it matches words. A match tells you a word appeared. It does not tell you whether the poster wants to buy, is complaining, is selling something, or is a student. That gap is why most people who start with a keyword alert end up with a full inbox and few conversations. The tools differ in how much of that sorting they do for you.
Choosing keywords
- Your brand name, so you can reply when someone mentions you.
- Competitor names, which catch people comparing or leaving.
- Problem phrases, the plain words a customer uses before they know your category exists. These find the most new leads.
Exact phrases are quieter and miss variations; broad words catch more and flood you with noise. Start narrow. Our list of 25 buying-intent phrases gives you starting material.
Method 1: Google Alerts with site:reddit.com
Create an alert for site:reddit.com "your phrase" and Google emails you new matches. It is free and takes a minute to set up. It is a general web alert rather than a Reddit tool, so treat it as a cheap extra rather than your main method.
Method 2: F5Bot
F5Bot emails you when a keyword appears on Reddit, Hacker News or Lobsters. To set it up, sign up, add your keywords, and confirm the email. The free plan is for personal use and allows 5 keywords and up to 20 alerts a day, delivered within about two hours. Paid plans start at $9.99 a month (Silver) and add faster alerts, more keywords and keyword filtering; AI filtering starts on the $49.99 Gold plan. See our F5Bot alternative page for a detailed comparison.
Method 3: Syften
Syften lets you write filters using words, quoted phrases and operators such as NOT, site:, title: and author:. It watches Reddit (posts and comments) plus many other sources, with a stated target Reddit delay of under a minute. Plans run $29.95, $49.95 and $119.95 a month with a 14-day trial. It rewards time spent tuning filters, and it suits people who need speed or several platforms. See our Syften alternative page.
Method 4: Intent-based tools
Tools such as Threadly and Redreach read each post and judge whether it is a genuine lead, so you review a ranked queue instead of raw matches. Threadly scans Reddit once a day, has Claude score buying intent, and drafts a reply for your approval. Redreach adds threads that rank on Google, mention tracking and DMs and starts at $19 a month. See our Redreach alternative comparison.
Method 5: Search by hand
Reddit search sorted by new, run once a day for each phrase. It costs nothing and gives you full control, but it eats time and does not scale beyond a few phrases.
Comparison
| Method | Cost | Speed | After the alert |
|---|---|---|---|
| Google Alerts | Free | Email digests from Google | You read and judge everything |
| F5Bot | Free; paid from $9.99/mo | Free plan within about 2 hours; paid within 5 minutes or faster | You read and judge everything; AI filtering from $49.99/mo |
| Syften | From $29.95/mo | Reddit delay targeted at under a minute | You read and judge; AI filtering on Standard and PRO |
| Threadly | $29/mo standard, 7-day trial | Once-a-day scan | Scored for buying intent; draft reply waits for your approval |
| Redreach | From $19/mo | Weekly tracking on the entry plan, daily on Growth | Suggested replies; you post yourself |
| By hand | Free | Whenever you search | You do everything |
Costs and speeds for F5Bot, Syften and Redreach are from each vendor's own site, checked September 21, 2026. Threadly scans once a day, so it is not the right tool if you need alerts within minutes.
How to cut noise, whichever tool you use
- Prefer phrases to single words.
- Exclude obvious false matches (add your own negative words where the tool allows).
- Restrict to the subreddits where your customers actually are.
- Ignore anything older than a few days unless it ranks on Google.
- Score each result before replying. A quick 1 to 5 is enough.
Which method to pick
- No budget: F5Bot free plus a daily manual search.
- You need speed or many platforms: Syften.
- You want a ranked queue and drafts, on Reddit only: Threadly or Redreach. See the full comparison.
Keep reading
- How to find leads on Reddit: a step-by-step guide
- F5Bot alternative
- Syften alternative
- Redreach alternative
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