Cloud & Infrastructure · head to head
Fly.io vs Lambda (AWS Serverless)
Lambda (AWS Serverless)
Cloud & Infrastructure
Run code without thinking about servers
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Fly.io egress is priced by destination region, from $0.02 per GB in North America and Europe to $0.12 per GB for Africa and India, so the same traffic costs six times more depending on where users are; Lambda (AWS Serverless) billed on two axes at once, $0.20 per million requests plus $0.0000166667 per GB-second of duration, so memory settings change the bill as much as traffic does
- They diverge on capability: Fly.io covers Global deployment, Lambda (AWS Serverless) covers Function-as-a-Service.
Where they differ
Only the attributes on which Fly.io and Lambda (AWS Serverless) actually diverge.
| Attribute | Fly.io | Lambda (AWS Serverless) |
|---|---|---|
| Platforms | Web, Api, Docker | Web, Api |
| Founded | 2020 | 2014 |
Identical on both: starting price (Free), pricing model (usage-based), free tier (Yes), user rating (Not yet rated), category (Cloud & Infrastructure).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Fly.io
- Global deployment
- Docker support
- Postgres databases
- Redis support
- Health checks
- Backups
- Monitoring
- Docker
Only in Lambda (AWS Serverless)
- Function-as-a-Service
- Event-driven execution
- Pay-per-use
- Multiple languages
- Concurrency limits
- Dead Letter Queues
- Environment variables
- API Gateway
Both cover
- Auto-scaling
- Cloud deployment
- Web support
What people use each for
The jobs each tool is most often brought in to do.
Fly.io
- Deploying containerised applications close to users across regionsnot Lambda (AWS Serverless)
- Running full stack apps and databases on managed machinesnot Lambda (AWS Serverless)
Lambda (AWS Serverless)
- Event-driven functions without managing serversnot Fly.io
- API backends behind API Gatewaynot Fly.io
- Processing S3, DynamoDB, SQS and Kinesis eventsnot Fly.io
- Scheduled jobs without a always-on instancenot Fly.io
- Edge compute through Lambda@Edgenot Fly.io
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Fly.io
- Egress is priced by destination region, from $0.02 per GB in North America and Europe to $0.12 per GB for Africa and India, so the same traffic costs six times more depending on where users are
- Stopped machines still bill at $0.15 per GB of root filesystem a month, so a paused service is not a free one
- Volumes are billed on provisioned capacity rather than usage, at $0.15 per GB a month
- Reservation discounts of 40% require paying a year up front, from $36 to $1,440
- Fly Kubernetes is a separate $75 a month per cluster
- Dedicated IPv4 addresses are $2 a month each
Lambda (AWS Serverless)
- Billed on two axes at once, $0.20 per million requests plus $0.0000166667 per GB-second of duration, so memory settings change the bill as much as traffic does
- Provisioned concurrency, used to avoid cold starts, is charged separately at $0.0000041667 per GB-second whether or not the function runs
- Ephemeral storage beyond the included 512 MB is metered
- Lambda@Edge costs $0.60 per million requests, three times the standard request rate
- VPC use and cross-region data transfer carry EC2 charges on top
Pricing, plan by plan
Fly.io
Free- FreeFree
- 3 shared-cpu-1x VMs
- 3GB persistence storage
- 160GB outbound data/month
- Pay-as-you-goFree
- Unlimited applications
- Dedicated machines
- Global deployment
Lambda (AWS Serverless)
Free- Free TierFree
- 1M free requests/month
- 400,000 GB-seconds/month
- Always free
Which should you pick?
Choose Fly.io if
- You need global deployment.
- You want to start without paying.
- You work on Web, Api, Docker.
- You also want docker support.
Choose Lambda (AWS Serverless) if
- You need function-as-a-service.
- You want to start without paying.
- You work on Web, Api.
- You also want event-driven execution.
Questions people ask
- Is Fly.io or Lambda (AWS Serverless) better?
- Neither clearly leads. Fly.io starts at Free and Lambda (AWS Serverless) at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Fly.io or Lambda (AWS Serverless)?
- Fly.io starts at Free and Lambda (AWS Serverless) at Free.
- Does Fly.io or Lambda (AWS Serverless) run on more platforms?
- Fly.io runs on Web, Api, Docker. Lambda (AWS Serverless) runs on Web, Api.
- Can I use Fly.io for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Fly.io best used for?
- Fly.io is most often used for deploying containerised applications close to users across regions, running full stack apps and databases on managed machines. Of those, deploying containerised applications close to users across regions and running full stack apps and databases on managed machines are not what Lambda (AWS Serverless) is typically brought in for.
- What can Fly.io do that Lambda (AWS Serverless) cannot?
- Fly.io covers Global deployment, Docker support, Postgres databases, Redis support. Lambda (AWS Serverless) covers Function-as-a-Service, Event-driven execution, Pay-per-use, Multiple languages. Both handle Auto-scaling, Cloud deployment, Web support.