Serverless Pricing & the Free Tier
Understand how AWS Lambda billing works, what counts toward cost, and how the generous free tier lets you build and experiment for almost nothing.
Serverless Pricing & the Free Tier is a free Serverless AWS Lambda Development lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Serverless AWS Lambda Development learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Pay Only for What You Use
With serverless you pay per request and per compute time, never for idle servers. When nobody calls your function, you pay nothing.
The Two Cost Components
Lambda cost has two parts: Requests (a flat price per million invocations) and Duration (billed per millisecond, scaled by memory).
GB-Seconds Explained
Duration uses GB-seconds: memory in GB times run time in seconds. More memory or longer runs cost more. Here is a quick estimator.
def estimate_gb_seconds(memory_mb, duration_ms):
memory_gb = memory_mb / 1024.0
duration_s = duration_ms / 1000.0
return memory_gb * duration_s
print(estimate_gb_seconds(512, 200))The Free Tier
The Lambda free tier gives 1 million requests and 400,000 GB-seconds every month — and it never expires after 12 months.
A Tiny Function is Nearly Free
A 128 MB function running 100 ms can serve millions of requests inside the free tier, making Lambda perfect for hobby projects and prototypes.
Memory Affects Cost and Speed
More memory also adds CPU, so sometimes more memory finishes faster and lowers total GB-seconds and cost. Always test — never assume.
Idle Costs Nothing
Unlike an always-on EC2 box, a deployed Lambda nobody calls costs zero compute. You only pay to store the code.
Watch the Hidden Costs
Lambda is cheap, but it triggers paid services: API Gateway requests, CloudWatch Logs storage, and data transfer all add to the bill.
Estimate Before You Build
Use the AWS Pricing Calculator to model monthly cost from invocations, average duration, and memory. Estimating early avoids surprises.
Set Billing Alarms
Set a billing alarm in CloudWatch or AWS Budgets so you get notified the moment spending crosses a threshold you choose.
Compare to Servers
For spiky or low-volume work, serverless usually beats an idle server. For steady, very high constant load, a reserved server can be cheaper.
Quick Check
Check your billing understanding.
Recap
Recap: Lambda costs per-request plus GB-seconds, has a big always-on free tier, trades memory for speed, and rewards estimating and alarms.
Frequently asked questions
Is the “Serverless Pricing & the Free Tier” lesson free?
Yes — the full text of “Serverless Pricing & the Free Tier” is free to read here on the web, and the Serverless AWS Lambda Development course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Serverless AWS Lambda Development course, upgrade to CoddyKit PRO.
What will I learn in “Serverless Pricing & the Free Tier”?
Understand how AWS Lambda billing works, what counts toward cost, and how the generous free tier lets you build and experiment for almost nothing. You practise Serverless AWS Lambda Development with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Serverless AWS Lambda Development?
No prior experience is required. Serverless AWS Lambda Development on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Serverless Pricing & the Free Tier” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Serverless AWS Lambda Development lesson?
Yes. Every Serverless AWS Lambda Development lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- What is Serverless Computing?
- Getting Started with AWS Lambda
- Your First Lambda Function
- Serverless Pricing & the Free Tier