How to Auto-DM Instagram Commenters for Free with n8n (Follow-Gate Included)

ManyChat charges $29/month for this. You can run it yourself for $0 in software. In this guide you’ll set up an n8n workflow that watches your Instagram comments, sends an automatic DM to anyone who comments a keyword, checks whether they follow you, and only then sends the link. It’s the same “comment GUIDE and I’ll DM it to you” flow big creators use – self-hosted, with no contact limits.

I built this for my own account (@khaitov.dev) and it runs in production. Everything below is what actually worked, including the problems I hit and how to fix them.

What the workflow does

1. Someone comments a keyword (for example GUIDE) on any of your posts or Reels.
2. n8n receives the comment through Meta’s official webhook within seconds.
3. The bot replies publicly under the comment (“Sent! Check your DMs 📩”) and sends a private DM with a button.
4. When they tap the button, the bot checks whether they follow you.
5. Following → they get the link. Not following → they’re asked to follow first, then tap “I followed ✅” to get it.
6. Every step is counted, so you can see how many comments, clicks, new followers and links each keyword produced.

Extras built in:

• Keywords are case-insensitive: guide, Guide! and GUIDE 🙏 all work.
• Several keywords can point to one link (handy for typos like PROMT).
• The same keyword can send a different link on a specific Reel.
• No duplicate DMs, even if Meta re-sends an event.
• The access token refreshes itself every week, so you never have to rotate it by hand.
• Normal DMs are left alone — the bot only reacts to its own keywords.

Is it really free?

The software is. n8n Community Edition is free to self-host with unlimited executions, and Meta’s Instagram API costs nothing. What you need is somewhere to run n8n with a public HTTPS address:

Avoid free hosts that put your app to sleep when idle. Meta’s webhooks arrive late or fail, and comments get missed.

What you’ll need

• An Instagram professional account (Creator or Business). Personal accounts can’t use the API.
• A free Meta for Developers account.
• n8n running on a public HTTPS domain (Meta rejects plain HTTP).
• A public privacy policy page on your website (needed in Step 6).
• About 45 minutes.

Step 0 — Run n8n with Docker (skip if you already have it)

On a fresh Linux server with Docker installed, point a subdomain such as n8n.yourdomain.com at the server’s IP, then create these two files in an empty folder.

docker-compose.yml

services:
  n8n:
    image: docker.n8n.io/n8nio/n8n
    restart: unless-stopped
    environment:
      - N8N_HOST=n8n.yourdomain.com
      - N8N_PROTOCOL=https
      - WEBHOOK_URL=https://n8n.yourdomain.com/
      - GENERIC_TIMEZONE=UTC
      - N8N_PROXY_HOPS=1
      - EXECUTIONS_DATA_SAVE_ON_SUCCESS=all
      - EXECUTIONS_DATA_PRUNE=true
      - EXECUTIONS_DATA_MAX_AGE=168
    volumes:
      - n8n_data:/home/node/.n8n

  caddy:
    image: caddy:2
    restart: unless-stopped
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./Caddyfile:/etc/caddy/Caddyfile
      - caddy_data:/data

volumes:
  n8n_data:
  caddy_data:
Caddyfile

n8n.yourdomain.com {
    reverse_proxy n8n:5678
}

Start it with docker compose up -d. Caddy gets an SSL certificate automatically. Open https://n8n.yourdomain.com and create your owner account.

Why these settings matter: WEBHOOK_URL makes n8n show your real domain instead of localhost in webhook URLs. The EXECUTIONS_DATA_* lines keep a 7-day history of successful runs. Without them, only failed runs are saved, which makes testing confusing.

Step 1 — Create the Meta app

1. Go to developers.facebook.com/apps → Create app.
2. Choose the Instagram use case (the one for managing messages and content on Instagram). Meta renames these options from time to time; pick the one that mentions Instagram API.
3. Open API setup with Instagram business login.
4. In Add required messaging permissions, make sure these three are enabled:
   • instagram_business_basic
   • instagram_business_manage_comments
   • instagram_business_manage_messages
5. In Generate access tokens, click Add account and log in with your Instagram professional account.
6. Copy two values: the account ID shown under your username (a long number starting with 1784…) and the token from Generate token.

⚠️ Treat the token like a password. Anyone who has it can send DMs from your account. Don’t paste it in chats, screenshots or public repos. If it leaks, remove the app under Instagram → Settings → Apps and websites, then generate a new token.

Step 2 — Allow message access in Instagram

In the Instagram app go to Settings → Messages and story replies → Message controls → Connected tools and turn on Allow access to messages. Without this, the API can’t send DMs.

Step 3 — Import and configure the workflow

1. In n8n: Create workflow → ⋯ → Import from file and pick the JSON you downloaded.
2. Open the Config node. It’s the only node you need to edit.

const CONFIG = {
  IG_USER_ID: '1784xxxxxxxxxxxx',        // account ID from Step 1
  ACCESS_TOKEN: 'IGAA...',               // token from Step 1
  VERIFY_TOKEN: 'any-long-random-string',// you'll paste this into Meta in Step 5
  API_VERSION: 'v23.0',
  ACCOUNT_HANDLE: '@your_handle',
  FAIL_OPEN: true,
  PUBLIC_REPLY: true,
  KEYWORDS: {
    GUIDE:  { title: 'free guide',  link: 'https://yoursite.com/guide' },
    PROMPT: { title: 'prompt pack', link: 'https://yoursite.com/prompts' },
  },
  ...
};

For VERIFY_TOKEN use something random. On macOS or Linux, openssl rand -hex 16 generates one.

3. Click Publish (older n8n versions: toggle the workflow to Active).

Check that it’s live. Open this in your browser, with your own domain and verify token:

https://n8n.yourdomain.com/webhook/ig-dm?hub.mode=subscribe&hub.verify_token=YOUR_VERIFY_TOKEN&hub.challenge=test123

If the page shows test123, you’re ready for Meta.

Step 4 — Understand the button and the fallback

Instagram only lets you check whether someone follows you after they’ve interacted with your DMs — a comment alone isn’t enough. That’s why the first DM includes a “Send me the link” button: tapping it gives the bot permission to check the follow and continue.

If Instagram ever rejects the button, the workflow automatically sends a text version instead: “Reply YES and I’ll send you the link”. Replying works exactly like tapping.

Step 5 — Connect the Meta webhook

1. In your Meta app, open Configure webhooks.
2. Callback URL: https://n8n.yourdomain.com/webhook/ig-dm
3. Verify token: the same VERIFY_TOKEN from the Config node.
4. Click Verify and save.
5. Under Webhook fields, subscribe to comments, messages and messaging_postbacks.
6. Make sure Webhook subscription is On for your account in the token section.

Click Test next to the comments field. A new execution should appear in n8n → Executions. Meta’s test event contains no keyword, so nothing gets sent — that’s expected.

Step 6 — Switch the app to Live (the step everyone misses)

This is where I lost the most time. While the app is in Development mode, Meta does not send you comments from other people. Meta’s Test button works, but your followers’ comments never arrive. The comments API even shows comments_count: 3 while returning an empty list.

You do not need App Review when you only use your own account. You only need to fill in the basics and switch to Live:

1. App settings → Basic: add your Privacy Policy URL, a User data deletion instructions URL (a section on the same page is fine), a category, an app icon (1024×1024) and a contact email. Save.
2. Switch App Mode from Development to Live (in newer dashboards: Publish in the left menu).

Your privacy policy must be publicly reachable. Open it in a private window to check, and if you use Cloudflare, make sure Bot Fight Mode isn’t blocking Meta’s crawler. It should say what Instagram data you receive (user ID, username, comment/message text, follow status), why, how long you keep it, and how people can ask for deletion.

Step 7 — Test it for real

1. From a different Instagram account, comment your keyword on any of your posts. Comments from your own account are ignored on purpose, so the bot never answers itself.
2. Within seconds you should see the public reply and a DM on the test account.
3. Tap Send me the link. If the test account doesn’t follow you, you’ll get the follow-first message. Follow, tap I followed ✅, and the link arrives.

See your stats

Open this URL (bookmark it, and don’t share it — it contains your verify token):

https://n8n.yourdomain.com/webhook/ig-dm?stats=YOUR_VERIFY_TOKEN

Customizing

Add a keyword for a new Reel

Add one line to KEYWORDS and click Publish:

PRICING: { title: 'freelance pricing sheet', link: 'https://yoursite.com/pricing' },

Tip: use a different keyword for each Reel. Your stats then show which video brought the leads.

Several keywords, one link (typos included)

Define the resource once, above const CONFIG = {, and reuse it:

const PROMPT_PACK = { title: 'prompt pack', link: 'https://yoursite.com/prompts' };

// inside KEYWORDS:
PROMPT:  PROMPT_PACK,
PROMPTS: PROMPT_PACK,
PROMT:   PROMPT_PACK,

Matching uses whole words, so add plural forms separately.

Same keyword, different link on one Reel

Use POSTS with the Reel’s media ID. Everything else falls back to KEYWORDS:

POSTS: {
  '17900000000000000': { GUIDE: { title: 'bonus guide', link: 'https://yoursite.com/bonus' } },
},

To list your media IDs, open this URL with your token:

https://graph.instagram.com/v23.0/me/media?fields=id,caption&access_token=YOUR_TOKEN

Change the wording

All DM texts live in the TEXT block of the Config node, and the public replies in PUBLIC_REPLIES. Keep several public-reply variations so they don’t look spammy. Set PUBLIC_REPLY: false to turn public replies off.

Limits you should know

• 750 comment DMs per hour per account. This is Meta’s cap on private replies to post and Reel comments. Follow-up messages (the follow-gate and the link) allow up to 100 per second.
• One private reply per comment, within 7 days. After that, you can keep messaging only if the person replies (a 24-hour window).
• No contact limits. Unlike ManyChat’s plans, the number of people isn’t capped. Only Meta’s API rate limits apply.
• If you ever go over 750 per hour on one viral Reel, the extra commenters won’t get a DM from this version. Add a queue if you expect that volume.

Troubleshooting

Got it running? Show me tag @khaitov.dev on Instagram. I share free tools and dev workflows like this every week.

Stuck on the server part, or want this set up for your account? Get in touch.