How 99market screens markets and calculates annualized return.

1. The market must be active, open, not archived and scheduled to end in the future.
2. The highest-priced outcome must display between 98.0¢ and 99.5¢, inclusive.
3. The market must report at least $1,000 in total volume.
4. Duplicate market IDs are removed and qualifying markets are ranked by APR, then by end time.

The filter is a discovery screen, not an endorsement. It does not prove that the displayed price is executable, the implied probability is accurate or the market will resolve as expected.

Simple return = (1 − purchase price) ÷ purchase price

APR = simple return ÷ (seconds to scheduled end ÷ 31,536,000)

99market uses simple annualization and assumes a $1 winning payout. It does not compound, estimate win probability or automatically deduct fees, slippage, taxes or settlement delay. APR can exceed 1,000% when a small potential return is divided by very little time.

Each feed row shows the favored outcome, current cached price, simple APR, scheduled time remaining, reported volume, reported liquidity and potential gross profit per $100 at the cached price. The original Polymarket link is the source for current order-book data and complete resolution rules.

The score uses two deterministic inputs: resolution clarity (45%) and market-specific realism (55%). It can reward objective sources and measurable thresholds and flag subjective language, rumors or common category-specific edge cases. Price, APR, volume and liquidity do not increase the score.

It is automated, may be incomplete and must not replace reading the market rules. See the full score methodology and limitations.

99market reads active markets from Polymarket's public Gamma API. A background refresh builds a cached snapshot, and pages render the last successful snapshot with a visible update time. The operational label indicates whether that cache is recent. Data can change after the timestamp, and API availability or classification errors can affect coverage.