Staxly

Loops vs Fly.io

Email marketing for SaaS — loops, transactional, campaigns in one
vs. Run your app close to users, globally

Loops websiteFly.io website

Pricing tiers

Loops

Free
1,000 subscribed contacts. 4,000 sends/month. All features. Loops footer on emails.
Free
Paid — 1.5k
1,500 contacts. Unlimited sends. No footer.
$15/mo
Paid — 5k
5,000 contacts. Unlimited sends.
$49/mo
Paid — 10k
10,000 contacts.
$99/mo
Paid — 25k
25,000 contacts.
$199/mo
Paid — 50k
50,000 contacts.
$349/mo
Custom
>100k contacts — contact sales.
Custom
Loops website

Fly.io

Pay-as-you-go
No monthly fee. Machines billed per second. Free allocations: ~3 small shared machines + 3 GB volumes.
$0 base (usage-based)
Shared CPU 1x — 256 MB
Entry VM. 1 shared vCPU, 256 MB RAM. ~$2.02/month continuously on.
$2/mo
Performance 1x — 2 GB
Dedicated 1 vCPU, 2 GB RAM.
$32/mo
Reservation — Shared (1 yr)
$36/year for $5/mo credit (40% savings).
$36/mo
Shared CPU 8x — 16 GB
8 shared vCPU, 16 GB RAM.
$89/mo
Performance 16x — 128 GB
Dedicated 16 vCPU, 128 GB RAM.
$1014/mo
Enterprise
Custom. Dedicated capacity, SLA.
Custom
Fly.io website

Free-tier quotas head-to-head

Comparing free on Loops vs pay-as-you-go on Fly.io.

MetricLoopsFly.io
No overlapping quota metrics for these tiers.

Features

Loops · 12 features

  • API KeysScoped keys for testing vs production.
  • Audiences (Segments)Filter contacts by properties + event behavior.
  • Campaign AnalyticsOpen/click/unsubscribe rates, heatmaps, A/B significance.
  • CampaignsOne-off broadcasts to audience segments. Schedule + A/B test subject.
  • ContactsContact records with custom properties (strings, numbers, booleans, dates).
  • Email EditorVisual block-based + Markdown + HTML modes.
  • EventsSend events to trigger loops/journeys or filter audiences.
  • Loops (Automations)Event-triggered automation flows with delays + conditions.
  • Mailing ListsOpt-in lists with subscribe/unsubscribe preferences per list.
  • Template LibraryPre-built templates for SaaS use cases (onboarding, digest, launch).
  • Transactional APISend transactional emails (receipts, password resets) via /transactional endpoin
  • WebhooksSubscribe to contact/event changes.

Fly.io · 14 features

  • Auto Stop/StartMachines auto-stop when idle, start on request (like scale-to-zero).
  • CertsLet's Encrypt + wildcard certs managed.
  • Fly GPUA100/L40S/A10 on-demand GPU machines.
  • Fly Kubernetes (FKS)Managed Kubernetes on Fly machines.
  • Fly MachinesFirecracker microVMs. Start in <1s. Run any Docker image.
  • Fly PostgresManaged Postgres via Supabase partnership (2024). Also legacy self-run Postgres
  • fly-replay headersRoute request to another region at app level.
  • Fly VolumesPersistent SSD attached to a Machine. Encrypted at rest.
  • Global AnycastSingle IP routes to the closest region automatically.
  • LiteFSDistributed SQLite with primary/replica across regions.
  • Private Networks6PN WireGuard mesh. Connect machines across regions privately.
  • SecretsEncrypted env vars propagated to all regions.
  • Tigris (partner)S3-compatible storage for Fly apps. By partner.
  • Upstash Redis (partner)Managed Redis via Upstash.

Developer interfaces

KindLoopsFly.io
CLIflyctl CLI
SDK@loops/loops, loops-py
RESTLoops REST APIMachines API
GRAPHQLFly GraphQL API
OTHERWebhooksFly Postgres (wire)
Staxly is an independent catalog of developer platforms. Some links to Loops and Fly.io may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.

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