Aster Chain · Oracle

The Aster Oracle

Every perpetual contract needs a reference price for liquidations, funding, and unrealized PnL. AsterDEX builds that price by aggregating 14 external exchanges, weighted by validator stake. This page explains the mechanic and why it matters when you size a position.

5 min read·Last reviewed May 2026
14External exchanges
MediannestedAggregation
Stake-weightedValidator votes
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The inputs

  • 14 external exchanges contribute price feeds for each market.
  • Each active validator independently observes those feeds.
  • The exact list of exchanges is documented on docs.asterdex.com.

The aggregation

  • Each validator computes a median across its observed exchange prices.
  • The chain takes the validator medians and produces a final mark price weighted by validator stake.
  • This nested median structure is robust: a single bad feed or a single malicious validator cannot move the mark price meaningfully.

What the mark price drives

  • Liquidation. Your position liquidates when your maintenance margin becomes insufficient at the mark price, not the last trade price.
  • Funding. The funding rate on perps tracks the mark price vs the trade price.
  • Unrealized PnL. Shown in the UI at the mark price.

RWA and pre-IPO oracles

  • For listed RWAs the oracle uses the official market price during trading hours and a reference index during off-hours.
  • For pre-IPO markets the oracle uses an aggregated signal (secondary valuations, analyst implied values). The exact methodology is per-market and documented per pair. See RWA Perps.

Why it matters when you trade

  • In fast moves, the mark price lags or leads the trade price depending on where most volume sits across the 14 venues.
  • You can be liquidated even if AsterDEX's own order book has not printed the liquidation price, because the mark price is calculated externally.
  • Conversely, brief wicks on a single venue cannot liquidate you because they are filtered out by the median.

Further reading

Last reviewed May 2026. Numbers drift — check the oracle feed for current values.

Corrections → @aster_scan