Gareth Wilson
Webhooks as a Service: Sending Providers Compared
Webhooks as a service is a hosted API that sends webhooks to your customers for you. You publish an event; the service delivers it to every customer endpoint subscribed to it, signs the request, retries failures, logs every attempt, and gives your customers a portal to manage their endpoints.
Four providers offer it, and each suits a different team:
- Hookdeck Outpost: the lowest price per event, delivery to queues and streams as well as HTTP, and an open-source (Apache 2.0) build identical to the managed service.
- Svix Dispatch: has the broadest feature set and PCI-DSS compliance. The most expensive per event.
- Convoy: one gateway for sending and receiving, aimed at teams that self-host. Source-available under the Elastic License 2.0.
- Hook0: a simple, EU-hosted service with an on-premise option. Source-available under SSPL v1.
The grid below compares all four on the same attributes. If you're looking for receiving infrastructure instead (webhooks coming in from Stripe, Shopify, or GitHub), see best webhook management platforms.
What a webhooks-as-a-service provider handles
Sending one webhook is an HTTP POST. Sending webhooks as a product feature means running all of this:
- An API to publish events, and fan-out from each event to every subscribed endpoint
- Multi-tenancy, so each customer has their own endpoints, secrets, and delivery history
- Topic subscriptions, so customers only receive the event types they ask for
- Signing, so customers can verify a request came from you
- Retries with backoff, and a decision about when to give up
- Endpoint health: alerts and auto-disabling for endpoints that keep failing
- A delivery log your support team can search
- A customer portal where customers add endpoints, rotate secrets, and retry failed deliveries themselves
You can build these on a queue and a worker pool. Our build vs buy guide walks through what that takes. A webhooks-as-a-service provider gives you all of it behind one API.
Webhooks-as-a-service providers compared
| Hookdeck Outpost | Svix Dispatch | Convoy | Hook0 | |
|---|---|---|---|---|
| Deployment | Managed (US, EU, Asia); self-hosted | Managed (US, EU, custom regions); open-source server | Managed cloud; self-hosted (Community or Premium) | Managed (EU); self-hosted; on-premise |
| Self-hosted licence | Apache 2.0. Same codebase as managed | MIT. README says some hosted features are missing | Elastic License 2.0 (source-available; was MIT until Aug 2024) | SSPL v1 (source-available) |
| Default retry policy | Exponential backoff, 30s base, 10 retries; custom schedule supported (docs) | 8 attempts over ~28 hours: immediately, 5s, 5m, 30m, 2h, 5h, 10h, 10h | Linear or exponential with jitter, set per project | 3s, 10s, 3m, 30m, 1h, 3h, 5h, then every 10h; stops at 24 attempts or 8 days |
| Signing scheme | HMAC-SHA256 in x-outpost-signature, or Standard Webhooks mode (docs) | HMAC-SHA256 in svix-signature (Standard Webhooks format); ed25519 option | HMAC in X-Convoy-Signature; hash and encoding set per project | HMAC-SHA256 in X-Hook0-Signature, with timestamp and signed headers |
| Destinations beyond HTTP | 10 native: SQS, S3, EventBridge, Kinesis, Pub/Sub, Service Bus, RabbitMQ, Kafka, Cloudflare Queues, Hookdeck Event Gateway (docs) | SQS, Pub/Sub, RabbitMQ, Redis via the separate Bridge component; object storage on Enterprise | None (HTTP only) | None (HTTPS only) |
| Customer portal | Themeable tenant portal, plus an API for building your own UI | Embeddable app portal; white-label on Professional and above | Portal links (a Premium feature when self-hosted) | Hosted portal with custom subdomain and logo |
| Multi-tenancy | One tenant per customer, each with its own destinations | One application per customer | Projects, with endpoints grouped by owner | Organisations and applications; subscriptions targeted by labels |
| Managed pricing | First 50K events free, then $10 per million; Growth $499/mo + $10 per million (pricing) | Free (50K messages/mo); Basic from $20/mo; Professional from $490/mo; $100 per million after 50K | Cloud Pro $99/mo; Cloud Premium $499/mo; self-hosted Premium $999/mo | Startup €59/mo (30K events/day); Pro €190/mo (100K/day) |
| Throughput limits | Uncapped | 50/s (Free), 200/s (Basic), 800/s (Professional) | Not published on pricing page | Daily event quotas per plan |
| Compliance listed by vendor | SOC 2 Type II, HIPAA (BAAs available), GDPR, CCPA, PIPEDA | HIPAA, PCI-DSS, GDPR, CCPA, PIPEDA; SOC 2 Type II report on Professional+; BAA on Enterprise | "SOC 2 & compliance support" on Enterprise | GDPR; hosted on Clever Cloud |
What it costs at your volume
Per-event pricing decides the bill once you pass a few million events a month. Using each vendor's published prices:
- 1 million events a month: Outpost about $9.50. Svix Basic about $115. Hook0 Startup's 30,000-a-day quota works out to roughly 900,000 a month, so at a steady 1 million you would need Pro (€190) or pay overage.
- 10 million events a month: Outpost about $99.50. Svix Basic about $1,015, and at that volume the 200-per-second Basic limit may push you to Professional (from $490 plus usage).
Convoy's cloud plans are flat monthly fees; check the event limits with Convoy before comparing them at volume.
How to choose a webhooks-as-a-service provider
Work through these in order. The first one you have a hard requirement on usually decides it.
- Compliance. If your procurement checklist includes PCI-DSS, Svix is the only provider here that lists it. If you need a HIPAA BAA, Hookdeck offers BAAs; Svix offers them on Enterprise.
- Where your customers want events. If some customers would rather receive events in their own SQS queue, Kafka topic, Pub/Sub subscription, or S3 bucket than run an HTTP endpoint, Outpost delivers there natively. Svix can reach some queues through Bridge. Convoy and Hook0 deliver over HTTP only.
- Self-hosting and licence. If you must run it yourself, decide whether a source-available licence (Convoy's ELv2, Hook0's SSPL) is acceptable to your legal team. If it isn't, your choices are Outpost and Svix. If you need the self-hosted build to match the managed one, Outpost is the one that states it does. Our open-source webhook tools roundup goes deeper on licences and dependencies.
- Volume. Above a few million events a month, the gap between $10 and $100 per million is the largest line item. Model your expected volume against each pricing page.
- Per-tenant controls. If you need FIFO ordering, per-endpoint throttling, payload transformations, or polling, Svix has them (some on Enterprise only). Outpost leaves these out by design and expects customers who need throughput control to use a queue destination.
- Who handles failed deliveries. Check whether customers can see and retry their own failed deliveries in the portal, whether you're alerted when an endpoint keeps failing, and whether failing endpoints are disabled automatically. All four retry automatically; they differ in how much of the recovery your customers can do without opening a support ticket.
The providers in brief
Hookdeck Outpost
Outpost covers the core of webhook delivery (multi-tenancy, topics, signing, retries, a delivery log, a customer portal, OpenTelemetry metrics) and delivers to 10 queue and stream destinations as well as webhooks. It costs $10 per million events with the first 50,000 free and no throughput cap. The managed service and the Apache 2.0 self-hosted build share one codebase.
Choose Outpost if cost at volume matters, if customers want events in their own cloud infrastructure, or if you want the option to self-host the same product later.
Read more: Hookdeck Outpost alternatives
Svix Dispatch
Svix has the widest feature set: transformations, connectors, FIFO ordering, polling, throttling, and gating webhook features behind your own paid plans. Several of these sit on Professional ($490/month) or Enterprise. Svix lists PCI-DSS compliance, which none of the other three do. The trade-off is price: $100 per million messages on paid plans, with throughput caps on each tier.
Choose Svix if you need PCI-DSS, or you need FIFO ordering, transformations, or polling and are happy to pay for Enterprise.
Read more: Svix Dispatch alternatives | Hookdeck Outpost vs Svix Dispatch
Convoy
Convoy handles both outbound and inbound webhooks in one gateway, and its strongest fit is self-hosting. Since August 2024 it has been licensed under the Elastic License 2.0 rather than MIT, and the free self-hosted Community edition covers the core gateway, with features such as RBAC, white-labelling, and JavaScript transformations reserved for the $999/month Premium licence. Delivery is HTTP only.
Choose Convoy if you want a single self-hosted gateway for both directions and the ELv2 licence and Premium pricing work for you.
Read more: Convoy alternatives for sending webhooks | Hookdeck Outpost vs Convoy
Hook0
Hook0 is a straightforward webhook sending service hosted in the EU, with self-hosted (SSPL) and dedicated on-premise options. Pricing is based on daily event quotas rather than per-event metering. Delivery is HTTPS only.
Choose Hook0 if you need EU-only hosting or an on-premise deployment managed with the vendor's help.
Read more: Hook0 alternatives | Hookdeck Outpost vs Hook0
Where Hookdeck Outpost fits
Outpost is built for SaaS and platform teams that need to offer webhooks and don't want delivery infrastructure to become a project of its own. It deliberately skips the features that make Svix's higher tiers expensive, on the bet that most teams would rather pay a tenth as much per event and handle transformations in their own code.
It is not the right choice for everyone. If PCI-DSS is on your checklist, or you depend on FIFO ordering or payload transformations inside the delivery layer, Svix fits better today.
To get started, follow the Outpost quickstarts for curl, TypeScript, Python, or Go, or self-host it with Docker.
Further reading
- Best open-source webhook tools
- Best webhook infrastructure platforms
- Why your platform needs outbound webhooks and how to ship them
- Outbound webhook retry best practices
Try Hookdeck Outpost for free
Send webhooks to any destination. First 50,000 events free, then $10 per million.
FAQs
What is webhooks as a service?
Webhooks as a service is a hosted API that sends webhooks to your customers on your behalf. You publish an event once; the service delivers it to every subscribed customer endpoint, signs each request, retries failures, keeps a delivery log, and usually gives your customers a portal to manage their endpoints. It replaces the queue, workers, retry logic, and dashboard you would otherwise build and run yourself.
What's the best webhooks as a service provider?
It depends on what you need most. Hookdeck Outpost is the lowest-cost option ($10 per million events) and the only one that delivers natively to queues and streams such as SQS, Kafka, and Pub/Sub; it is also open source under Apache 2.0. Svix Dispatch has the broadest feature set, including transformations, FIFO ordering, and PCI-DSS compliance. Convoy suits teams that want one self-hosted gateway for sending and receiving. Hook0 suits EU-based teams that want on-premise deployment.
What are the best webhooks-as-a-service platforms for SaaS companies?
For most SaaS companies adding webhooks to their product, the shortlist is Hookdeck Outpost and Svix Dispatch. Both provide multi-tenant delivery, signed requests, automatic retries, and an embeddable customer portal. Outpost costs about a tenth as much per event and supports non-HTTP destinations; Svix offers more advanced features on its higher tiers and holds PCI-DSS compliance.
Is webhooks as a service the same as a webhook gateway?
Not quite. Webhooks as a service usually means outbound delivery: your platform sending events to your customers. A webhook gateway usually means inbound: receiving webhooks from providers like Stripe or Shopify, verifying them, queueing them, and routing them to your services. Hookdeck sells both as separate products: Outpost for sending and Event Gateway for receiving.
Can I self-host webhooks as a service?
Yes. All four providers in this comparison publish their source code. Hookdeck Outpost (Apache 2.0) and Svix (MIT) use OSI-approved open-source licences. Hook0 uses SSPL v1 and Convoy uses the Elastic License 2.0, which are source-available licences with restrictions. Outpost's self-hosted build is the same codebase as its managed service; Svix says its open-source server lacks some features of the hosted version.
