Tick size

Tick size is the minimum price increment at which an instrument can trade, as published in its contract specification. Every quoted price is a whole number of ticks, so tick size defines the price grid on which a footprint's rows, a DOM's levels and a heatmap's cells are built.

Senzoukria · Glossary · Updated September 2026

The price grid

Because no trade can occur between two ticks, tick size is the natural unit for anything measured in price: the gap between two bars, the distance between two points of control, the width of a bar's range. Working in tick indices rather than raw prices also keeps comparisons exact; a difference of four ticks expressed in floating-point price can round to slightly less than four and fail a threshold that it should pass. The site's MNQ guide gives the published minimum price fluctuation of the Nasdaq-100 futures as 0.25 index points, so four ticks make one point.

Aggregation: ticks per row

  • A footprint row can hold one tick or several. Grouping ticks per row is a readability choice: the executions are unchanged, only the number of rows and the diagonals computed across them change.
  • On a fast contract with a small tick, one tick per row spreads volume over many thin rows; a coarser aggregation concentrates it. Imbalance ratios computed diagonally, in the ATAS convention, therefore depend on the aggregation and must be re-checked when it changes.
  • A heatmap's vertical resolution is also a multiple of the tick, and the DOM shows one level per tick by definition.

In Senzoukria

The tick size of each instrument comes from the instrument catalogue. When it is unknown the desktop shows a message stating that the price grid is unknown, that history is not being cached and that adding the tick size to the catalogue fixes it. Several v2 indicators declare the data they require as Aggregated price levels and instrument tick size or OHLC bars and instrument tick size, and produce no output without it; the note on the POC migration distance study, for example, states that it is measured in ticks and requires a known tick size. The Gap Open overlay draws nothing when the tick size is missing, because a threshold in ticks has no meaning without a grid.

Common mistakes

  • Confusing tick size with tick value. The first is a price increment; the second is what that increment is worth per contract in currency.
  • Transferring an imbalance threshold between two contracts with different tick sizes or different aggregation.
  • Letting a tool fall back to a guessed grid. A fallback quantiser can turn one real tick into thousands of false ones; the correct behaviour is to degrade to no output.

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Frequently asked questions

Is tick size the same for every futures contract?
No. Each contract specification publishes its own minimum price fluctuation, and some products even have different ticks for outright trades and for spreads. Always read the tick from the exchange specification for the exact contract, not from a related product.
What does price aggregation change on a footprint?
Only the presentation. Grouping several ticks into one row merges the bid and ask volume of those ticks into a single cell. The trades are the same; the row count, the visual density and any diagonal comparison across rows are different. Keep the aggregation fixed across a sample when tuning thresholds.
Why is my crypto chart's history not being cached?
Most likely because the pair's tick size is not known to the instrument catalogue. Without a price grid the chart cannot store levels reliably, so it re-downloads the history on each load and tells you so. Adding the tick size to the catalogue resolves it.

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