Essential building blocks: HTTP Request, IF, Set, Merge, Code node (even if you don’t code)
If n8n workflows are a city, then n8n core nodes like HTTP Request, IF, Set, Merge, and Code are the roads, traffic lights, and bridges that keep everything moving. Learn these five once, and 80% of your future automations for SaaS and agencies will suddenly make sense.
In Day 6 of 30 Days of n8n & Automation, this guide walks through what each n8n core node does, how they fit together, and how to use them even if you “don’t code”.
Why n8n core nodes matter
Most people get lost in the endless list of integrations and ignore the n8n core nodes that actually shape their workflows. Once you’re comfortable with these, adding apps is just “decoration”.
Think of it like this: tools (Slack, Notion, HubSpot) are apps on your phone, but n8n core nodes are the operating system.
HTTP Request: talk to any API
The HTTP Request node is how n8n talks to the outside world when there isn’t a dedicated integration yet.
- Use it to call SaaS APIs (CRMs, billing, custom apps) with GET/POST/PATCH/DELETE.
- With good naming and a saved credential, it becomes your “universal plugin” for almost anything.
Best practice: start by copying working requests from Postman or the API docs, then paste URLs and payloads into your n8n core node instead of guessing.
IF: your workflow’s decision maker
The IF node is a simple yes/no gate that decides what should happen next based on conditions you set.
- Use it to check lead quality, payment status, onboarding steps, or error flags.
- For SaaS and agencies, classic checks are: “is trial active?”, “is ARR > X?”, “is onboarding form complete?”.
Best practice: keep IF conditions human‑readable and close to business logic, not weird technical flags no one understands a month later.
Set: clean and shape your data
The Set node is like a tiny spreadsheet cell editor inside your n8n core nodes toolkit.
- Rename fields to something meaningful (email → customerEmail).
- Remove noisy fields you’ll never use.
- Add new fields like tags, timestamps, or normalized values.
Using Set early keeps your workflow readable and makes later nodes much easier to work with, especially when you’re merging data or sending it to external tools.
Merge: combine multiple data streams
Whenever you need data from two paths at once, the Merge node is your friend.
Examples for SaaS and agencies:
- Merge subscription data from Stripe with customer data from your CRM.
- Merge ad platform results with internal cost data for reporting.
Key modes inside this n8n core node:
- Append: just stack results.
- Merge by key: like a JOIN in SQL (great for matching users by ID or email).
- Enrich Input: keep one stream and add matching data from the other.
Code: tiny logic upgrades (even if you don’t code)
The Code node sounds scary if you’re “not technical”, but for most SaaS/agency use cases it’s just small JavaScript helpers.
Good use cases:
- Clean up strings (trim spaces, lowercase emails).
- Build custom IDs or slugs.
- Do small calculations that would be painful with only UI nodes.
Start small: copy a known snippet from docs or community, change the variables, and log the output. You don’t need to be a full developer to get huge value from this n8n core node.
How these n8n core nodes work together
A typical SaaS/agency workflow often looks like this:
- HTTP Request node: pull data from your SaaS, CRM, or billing.
- Set node: clean and standardize the fields.
- IF node: branch based on business rules (who gets what next).
- Merge node: bring in data from another source if needed.
- Code node: apply any extra logic that UI nodes can’t easily express.
Notice how app‑specific nodes just plug into this backbone; the real structure comes from the n8n core nodes.
What to practice next
To really learn these n8n core nodes, build one tiny workflow for each:
- HTTP Request: fetch your own data (e.g., list of deals or invoices).
- IF: route records based on a threshold or status.
- Set: rename and clean fields before using them.
- Merge: combine data from two HTTP Request calls.
- Code: write a 3–5 line snippet that changes one field and logs the result.
Do this once, and almost every future n8n tutorial, template, or community post will feel 10x easier to follow.