USDT Market Cap
Tether market-cap (liquidity proxy).
What it measures
Tether's circulating market capitalization (CoinGecko), served as a slow liquidity proxy. Stablecoin supply is the on/off-ramp of crypto: sustained issuance means new dollars are parked on the rails and deployable, contraction means dollars are leaving the system. It moves on a scale of hours to days, which is why it is served on the 1h-and-up windows only — context for slower models, not a trading trigger.
References: Stablecoin on/off-ramp proxy.
Point-in-time, leak-free
Like every QUANT_API feature, context.usdt_mcap is computed point-in-time: each value uses only data that had actually arrived at the timestamp you query — live or historical. No restatements, no backfills that quietly rewrite the past, no look-ahead. The value your backtest sees at a given stamp is the value the live API would have returned at that stamp. How we enforce this is documented on the methodology page.
Windows & transforms
The signal is computed over rolling windows; each window can be served raw or through a transform (z-score, percentile rank, delta…). Which windows and transforms you can query depends on your plan — the signal itself supports:
Plan & access
context.usdt_mcap unlocks on the Signal plan ($99/mo) and every plan above it. Every new account starts with a 14-day free trial of the Signal plan — no card required.
Example call
Resolve the latest value for BTC (1h window, delta transform — both available on the Signal plan):
curl -G https://api.quant-api.dev/v1/features/live \
-H "Authorization: Bearer fk_live_<your_key>" \
--data-urlencode "asset=BTC" \
--data-urlencode "features=context.usdt_mcap@1h:delta"Same key works on /v1/features/historical for point-in-time backtesting — see the API docs.