Aperiodic Indices · Cost

What does crossing the spread cost?

The Aperiodic Cost Index is the bid-ask spread in basis points of the mid price, for crypto and RWA perps.

Shown: the median perpetual’s dollar depth at the top of the book, as a share of its 20:00–20:45 average, per venue, 18:00–01:00 UTC on 10 Oct 2025; minutes under half of normal take the strong tone, and the lowest of all, OKX’s 26.1% at 22:33, is orange · built with l1_liquidity 1m

Aperiodic Cost Index

Binance’s BTC-USDT perp, then the busiest perps in crypto, US stocks and commodities.

Aperiodic Cost IndexBitcoin USDT perpetual on Binance: 0.013bps

Crypto

Contract	Cost
Bitcoin USDT perp · Binance	0.013bps
Ether USDT perp · Binance	0.044bps
Bitcoin USDT perp · OKX	0.013bps
Ether USDT perp · OKX	0.044bps
Bitcoin USDC perp · Hyperliquid	0.13bps
Bitcoin USDC perp · Binance	0.013bps

US stocks

Contract	Cost
SanDisk USDT perp · Binance	0.089bps
SanDisk USDT perp · OKX	0.89bps
Micron USDT perp · Binance	0.12bps
S&P 500 USDC perp · Hyperliquid	0.13bps
Alphabet USDT perp · Binance	0.36bps
Nasdaq 100 ETF USDT perp · Binance	0.15bps

Commodities

Contract	Cost
Gold USDT perp · Binance	0.025bps
Silver USDT perp · Binance	2.0bps
WTI crude oil USDT perp · Binance	1.0bps
Brent crude oil USDT perp · Binance	0.97bps
Gold USDT perp · OKX	0.25bps
WTI crude oil USDC perp · Hyperliquid	0.11bps

Get the Aperiodic Cost Index

In the APIl1_liquidity.spread_bps

For every perp we cover, at intervals from 1 minute to 1 day.

In Prime and up, from $399/month billed yearly.

Get it with Prime See the dataset

The example needs no key and returns the free sample: BTC-USDT on Binance, 5m bars, May 2025.

# Install the Aperiodic CLI into ~/.local/bin
mkdir -p "$HOME/.local/bin"
curl -fsSL https://raw.githubusercontent.com/aperiodic-io/cli/main/install.sh | INSTALL_DIR="$HOME/.local/bin" bash
export PATH="$HOME/.local/bin:$PATH"

# Free preview — no API key required
aperiodic l1_liquidity --preview \
  --exchange binance-futures \
  --symbol perpetual-BTC-USDT:USDT \
  --interval 5m \
  --timestamp exchange \
  --start-date 2025-05-01 \
  --end-date 2025-05-31 \
  --output-dir ./data && echo "Saved to $PWD/data"

Best and worst contracts

The 383 contracts with at least $10M of 24-hour volume, ranked by cost.

Cheapest to trade

Contract	Venue	Cost	24h volume
Bitcoin USDT	Binance	0.013 bps	$16.14B
Bitcoin USDT	OKX	0.013 bps	$9.47B
Bitcoin USDC	Binance	0.013 bps	$4.03B
Gold USDT	Binance	0.025 bps	$2.87B
PAXG USDT	Binance	0.025 bps	$123.2M
XAUT USDT	Binance	0.025 bps	$58.2M
Ether USDT	OKX	0.044 bps	$9.28B
Ether USDT	Binance	0.044 bps	$10.70B
Ether USDC	Binance	0.044 bps	$2.80B
Zcash USDT	OKX	0.082 bps	$2.01B

Most expensive to trade

Contract	Venue	Cost	24h volume
AKE USDT	OKX	28 bps	$70.1M
INTW USDT	Binance	16 bps	$131.8M
SNXX USDT	Binance	16 bps	$420.3M
AXIS USDT	OKX	14 bps	$21.0M
NET USDC	Hyperliquid	12 bps	$11.4M
KIOXIA USDC	Hyperliquid	11 bps	$16.8M
UAI USDT	Binance	11 bps	$39.7M
SNXX USDC	Hyperliquid	9.7 bps	$12.3M
HUMA USDT	OKX	9.7 bps	$30.4M
FLUID USDT	Binance	9.2 bps	$19.3M

Method

Best ask minus best bid, in basis points of the mid price (l1_liquidity.spread_bps).
A contract’s value is the median of its last 24 hours of 5-minute rows. The chart plots those rows.
The API serves the same column at every interval the dataset has.

Columns it reads

spread_bpsL1 Liquidity

The other indices

Aperiodic Depth IndexHow much is quoted at the best bid and ask?Aperiodic Impact IndexHow far does $1M of net taker flow move the price?

As of 15:05 UTC, 15 minutes behind. Each value is one contract’s last 24 hours of 5-minute rows. The charts plot those rows.