Reddit Keyword Monitoring: The Free Ways That Still Work
F5Bot's current free limits, why Reddit's search RSS trick stopped working, and what Google Alerts and HN Algolia actually cover, checked October 2026.
By The Larvabot team7 min read
F5Bot is still the fastest free way to get an email the moment someone mentions your keyword on Reddit, Hacker News or Lobsters — five keywords, no credit card, checked directly on its site this month. The trick you've probably read about, subscribing to a Reddit search as an RSS feed, no longer works without logging in as of October 2026. Google Alerts barely touches Reddit at all. Here's what's actually free right now, and how to pick keywords that catch real buying questions instead of noise.
What's the actual free way to monitor Reddit for your keywords?
| Method | Keyword limit (free) | Covers | Alert delay | Needs a Reddit account? |
|---|---|---|---|---|
| F5Bot | 5 keywords | Reddit, Hacker News, Lobsters | Up to 2 hours | No |
| Subreddit RSS feed | Unlimited subreddits, but no keyword filter | One subreddit's new posts only | As fast as your RSS reader polls | No |
| Reddit's own keyword search (RSS) | — | Reddit only | — | Now requires login |
| HN Algolia search | Unlimited queries, no alerts built in | Hacker News only | Manual (you have to check) | No |
| Google Alerts | Unlimited | Whatever Google has indexed, rarely fresh Reddit threads | Hours to days | No |
Is F5Bot still free, and what do you actually get?
Yes. F5Bot's own pricing page lists its Free tier at $0, described as "free forever," with no credit card required. The Free plan currently includes:
- 5 keywords, each capped at 10 matches a day, for 20 total daily alerts.
- Coverage of Reddit, Hacker News and Lobsters — no other platforms.
- Alerts delivered by email with up to a 2-hour delay (paid tiers drop this to 5 minutes or instant).
- 7 days of match history.
- No full post text in the free alert email, no keyword filtering flags, and no RSS/JSON export — those start on the $9.99/month Silver tier.
Setup is genuinely three steps: make a free account with just an email address, add the words or phrases you want to track, and you'll get an email the next time one of them shows up in a new post or comment. Five keywords is plenty if you track your product name, a couple of close misspellings, and one or two problem phrases your buyers actually type ("looking for a tool that," not just your brand) — the same kind of phrase-matching that works for finding your first 100 users on Reddit in the first place.
Can you still monitor Reddit keywords for free with an RSS feed?
Partly, and this is where a lot of older advice is now out of date. Testing both this month:
- A single subreddit's post feed still works without logging in.
reddit.com/r/<subreddit>/.rssreturns every new post in that subreddit as a standard Atom feed — no login wall, confirmed working in October 2026. Point an RSS reader at a handful of subreddits where your buyers hang out, and filter for your keywords inside the reader if it supports that. - Reddit's keyword search as an RSS feed no longer works. The old trick — appending
/search.rss?q=yourkeywordto a subreddit or to reddit.com itself — now redirects straight to Reddit's login page instead of returning a feed, confirmed by fetching it directly this month. If a guide still tells you to build alerts this way, it's describing a method that no longer works for a logged-out request.
That leaves subreddit-level RSS as a free, login-free option for watching specific communities in bulk, but it's not a keyword filter on its own — you still have to scan (or set up a reader rule for) every new post in each subreddit you add.
Does Google Alerts catch Reddit mentions?
Rarely in time to be useful. Google's own Alerts help page describes it as emailing you "when new results for a topic show up in Google Search" — it doesn't mention forums or Reddit specifically, and in practice it surfaces Reddit threads only once Google has crawled and indexed them, which can take anywhere from hours to days after a post goes up. By the time an alert arrives, the thread is often already answered. Treat Google Alerts as a backup for your brand name across the open web, not a Reddit monitoring tool.
What about Hacker News specifically?
HN's own Algolia-powered search is free, public, and doesn't need an API key — you can query it by keyword and sort by date to see the newest matches first. What it doesn't have is a built-in email alert or RSS feed for a saved search, so you'd be checking it manually. Since F5Bot already covers Hacker News on its free plan with the same five keywords you're using for Reddit, there's rarely a reason to build your own HN watcher on top of the Algolia API — use F5Bot for the alert and Algolia's search only when you want to dig through HN's history by hand.
How do you pick keywords that catch real buying questions, not noise?
The keyword that catches the most mentions is usually your product name — and it's also the least useful one, because most of what gets said about an unknown product is nothing at all. Track phrases people type when they have the problem you solve, not just your brand:
- Use the words a buyer uses, not a marketer's phrase: "is there a tool that tracks," "any alternative to [bigger competitor]," "how do I automate," not your tagline.
- Add the misspellings and shorthand people actually type for your own name (a slash, missing hyphen, or common typo) alongside the correct spelling.
- Skip single common words — "notes" or "tasks" alone floods five keyword slots with false positives on a free F5Bot plan. Pair them with a qualifier ("notes app recommendation").
- Review your first week of matches and drop anything that's mostly noise; a free plan's five slots are worth spending on phrases that convert, not ones that just mention a category.
What do good and bad keywords actually look like?
| Keyword type | Good example | Why |
|---|---|---|
| Problem phrase | "any tool that tracks mentions" | Matches people mid-search, before they've named a product |
| Competitor name | "f5bot alternative" | Catches people already shopping, actively unhappy, or comparing |
| Your product name + common typo | "larvabot" and "larva bot" | Covers the split-word version people type without thinking |
| Bad: single common noun | "notes" or "leads" alone | Floods a 5-keyword free plan with unrelated posts |
| Bad: your tagline | "find your next customer" | Nobody searches in marketing copy; real posts use plain problem language |
If you're watching a handful of subreddit .rss feeds in an RSS reader, look for a "must contain" or keyword-filter rule per feed so you're not reading every new post by hand — most readers that support custom feeds have one, but the exact setting and what it's called varies by app.
How do you reply once an alert lands in your inbox?
Fast, and within the subreddit's own rules — a generic alert tool doesn't make a reply welcome if it reads like an ad. Our guide on how to promote on Reddit without getting banned covers the self-promotion rules and how to write a reply that answers the question first. Larvabot builds on the same free alert idea: its Reddit watch scores new posts for fit and drafts a reply you edit and post yourself, with F5Bot-style alerts supported directly if you'd rather keep using the account you already have (how the Reddit watch works, F5Bot alerts in Larvabot).
Frequently asked questions
Is there a true F5Bot alternative with more free keywords?
Not one with a materially larger free allowance that monitors the same three sources (Reddit, Hacker News, Lobsters) — F5Bot's free tier (5 keywords, 20 alerts a day) is the one checked for this piece. Pairing it with a few subreddit RSS feeds for your most important communities extends free coverage without needing a paid plan.
Why did my Reddit search RSS feed stop working?
As of this month, requesting a Reddit keyword search as an RSS feed (/search.rss?q=...) redirects to Reddit's login page instead of returning results — confirmed by testing it directly. A single subreddit's post feed (/r/<subreddit>/.rss) still returns without logging in; it's the search-specific feed that's now gated.
Does F5Bot read private subreddits or DMs?
No — it only sees what's public on Reddit, Hacker News and Lobsters, the same as anyone browsing logged out. It can't alert you to anything inside a private or restricted subreddit.
How many keywords do I actually need?
Most solo founders do fine with 3–5: your product name, one or two common misspellings, and one problem phrase your buyers use before they've heard of you. That fits inside F5Bot's free 5-keyword limit without upgrading.
Is Google Alerts worth setting up at all?
Yes, just not for Reddit. It's still useful as a free, low-effort catch-all for your brand name across news sites, blogs and anywhere else Google crawls — keep it running alongside F5Bot rather than instead of it.