Single secure WebSocket endpoint multiplexing every subscription via tilde-delimited subscription strings (e.g. 5~CCCAGG~BTC~USD). Channel types: Trade (0), Ticker (2), Aggregate Index / CCCAGG (5), Order Book L2 update (8), Order Book L2 snapshot (9), Full Volume (11), Top Tier Full Volume (21), OHLC Candles (24), and Top of Order Book (30). Control envelopes include Welcome (20), SubscribeComplete (16), UnsubscribeComplete (17), LoadComplete (3), UnsubscribeAllComplete (18), Heartbeat (999), Unauthorized (401), RateLimit (429), and ServerError (500).
CryptoCompare Streaming WebSocket is one of 18 APIs that CryptoCompare publishes on the APIs.io network, described by an AsyncAPI event-driven specification.
Tagged areas include Cryptocurrency, Streaming, WebSocket, Order Book, and OHLCV. The published artifact set on APIs.io includes API documentation and an AsyncAPI specification.
This event API exposes
2 operations
across 1 channel,
and defines 38 schemas.
It is described by AsyncAPI 2.6.0, at version 2.0.
The API connects through a single server, streamer.cryptocompare.com/v2 (wss).
2 operations1 channels38 schemas
Metadata
The identity and technical contract details declared by the specification.
Across 1 channel, the API surfaces 2 operations. Each is listed below with its action, channel, parameters, and response codes.
Channels 2
SUB
/
Receive welcome, lifecycle, heartbeat, error, and data envelopes.
serverEventsbody
PUB
/
Send a SubAdd or SubRemove action to manage subscriptions.
clientActionbody
Messages & Schemas 38
The contract defines 38 schemas that model the data carried by its messages. The most detailed are Ticker (31 properties), Welcome (20 properties), OHLCCandles (20 properties), Trade (14 properties). Each schema is shown below with its type and property counts.
SubAdd
message
Add one or more subscriptions to the current socket.
SubRemove
message
Remove one or more subscriptions from the current socket.
Welcome
message
First frame sent after a successful socket upgrade.
SubscribeComplete
message
Subscription done and first payload sent.
LoadComplete
message
All subscriptions done and all payloads sent.
UnsubscribeComplete
message
Subscription removal done.
UnsubscribeAllComplete
message
All subscription removals done.
Heartbeat
message
Liveness ping sent by the server every 30-60 seconds.
Unauthorized
message
API key missing, invalid, or lacks access to a requested channel.
RateLimit
message
Socket open / subscription rate-limit notice.
ServerError
message
Invalid JSON, invalid subscription, or forced disconnect notices.
Trade
message
A single trade reported by an exchange.
Ticker
message
Per-exchange ticker snapshot and delta.
AggregateIndex
message
CryptoCompare CCCAGG (or other index family) update.
OrderbookL2Update
message
Single-position delta to a level-2 order book.
OrderbookL2Snapshot
message
Full level-2 order book snapshot at subscribe time.
FullVolume
message
Rolling 24-hour total volume across all markets for a base.
TopTierFullVolume
message
Rolling 24-hour total volume across top tier exchanges (AA/A/B).
OHLCCandles
message
Streaming minute / hour / day OHLCV candle updates.
TopOfBook
message
Best bid / best ask updates for a market.
SubActionEnvelope
object
3 properties2 required
Welcome
object
Streamer Welcome (TYPE 20) envelope. Field availability follows the documented mask bits when the streamer (non-JSON) format is used; with apikey JSON every fi…
20 properties7 required
SubLifecycleEnvelope
object
Subscribe / unsubscribe lifecycle envelope (TYPE 16 or 17).
3 properties3 required
InfoEnvelope
object
Generic INFO envelope (LOADCOMPLETE TYPE 3 and similar).
3 properties2 required
UnsubscribeAllEnvelope
object
Unsubscribe-all complete envelope (TYPE 18).
4 properties2 required
Heartbeat
object
Server heartbeat (TYPE 999).
3 properties2 required
AuthErrorEnvelope
object
Unauthorized envelope (TYPE 401).
4 properties2 required
RateLimitEnvelope
object
Rate-limit envelope (TYPE 429).
4 properties2 required
ServerErrorEnvelope
object
Server error envelope (TYPE 500).
4 properties2 required
Trade
object
Trade update (TYPE 0). Streamer-format unpack uses the bitmask below; with JSON every present field is emitted directly.
14 properties5 required
Ticker
object
Ticker update (TYPE 2). Same envelope is reused for some AggregateIndex fields.
31 properties5 required
AggregateIndex
object
OrderbookL2
object
Order Book L2 update (TYPE 8).
12 properties9 required
OrderbookL2Snapshot
object
Order Book L2 snapshot (TYPE 9), seeded on subscribe.
7 properties5 required
FullVolume
object
Full Volume (TYPE 11). Rolling 24-hour volume across all markets.
3 properties3 required
TopTierFullVolume
object
Top Tier Full Volume (TYPE 21). Same as Full Volume but limited to AA/A/B exchanges.
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