# Fathom Levels High, low, open, close, POC and value area of sessions, weeks and months. ## What the indicator shows - For each session, week and month: open (O), high (H), low (L), midpoint (MP) and, for past periods, close (C). - For sessions and weeks: POC (P), 70% value area (VH / VL) and VWAP (VW). - Current period levels move; past period levels are fixed. ## How to use it - The previous period’s extremes and close act as support and resistance: watch how price reacts when it reaches them. - The previous session’s POC and value area show where the market accepted price. Price settling outside that area is looking for a new value. - Use `days`, `weeks` and `months` to choose how many periods to keep on screen. In `confirmed` mode, count the current period: `weeks: 2` to receive the previous week. ## How it is computed - Publishes the last `days` sessions, `weeks` weeks and `months` months, current period included. `days`, `weeks` and `months` cannot all be 0. - A session runs from 6:00 pm to 5:00 pm New York time; a week, from Sunday 6:00 pm to Friday 5:00 pm; a month groups the sessions that open during that month: the session of October 1, 2026 opens on September 30 at 6:00 pm, so it counts in September. - Levels are computed on finished `timeframe`-second bars. The close `C` only exists for past periods. The POC, the value area (70% of the volume, built like `session-profile`’s) and the VWAP are only published for sessions and weeks. - On an alias (`NQ.front`), periods before the last rollover are computed on the current contract, thinly traded at the time: their levels are not very representative. ## When it updates - Levels of the current period are sent in progress (`current: true`) and updated on every finished bar. - The period change is processed when the first bar of the new session closes (6:05 pm with `timeframe: 300`, 7:00 pm with `timeframe: 3600`): the levels of the period that ends are sent final, with the close `C`, if they stay in the window; those leaving it are removed (`remove`, with `final: true`). - With a count of 1 (`weeks: 1` by default, or `days: 1`), the only period published is the current one: its levels never become final and are removed when the period changes. In `confirmed` mode you therefore receive no level of that period, only their `remove`s (ignore a `remove` for an unknown `id`); use `weeks: 2` to get the previous week. With `skipCurrent`, a count of 1 publishes nothing. - No reset: past periods stay published while they are in the window. - **Identifier**: `key-levels` - **Objects received**: `level` - **Historical cost**: 1 compute unit per trade ## Subscribe The same `params` work in [real time](https://fathomcharts.com/docs/websocket.md), on [historical data](https://fathomcharts.com/docs/history.md) and in exports. Parameters you omit take their default values. **Subscribe message** ```json { "t": "subscribe", "sub": "key-levels", "instrument": "NQ.front", "indicator": "key-levels", "params": { "days": 2, "months": 0, "skipCurrent": false, "timeframe": 300, "weeks": 1 }, "mode": "live", "from": "live" } ``` ## Parameters As soon as a parameter differs from its default, the subscription counts as a [custom configuration](https://fathomcharts.com/docs/limits.md#how-limits-are-counted). To change a parameter, open a new subscription. | Parameter | Type | Default | Allowed values | Unit | Description | | ------------- | ------- | ------- | ----------------------------------------------------------------------------------------------- | ---- | ------------------------------------------------------------------------------------------------------------------------------ | | `days` | integer | `2` | 0 to 30 | — | Number of sessions published, current session included. `days`, `weeks` and `months` cannot all be 0. | | `months` | integer | `0` | 0 to 12 | — | Number of months published, current month included (no POC, value area or VWAP). `days`, `weeks` and `months` cannot all be 0. | | `skipCurrent` | boolean | `false` | true · false | — | Hide the levels of the current period. | | `timeframe` | integer | `300` | `1` · `5` · `10` · `15` · `30` · `60` · `120` · `180` · `300` · `600` · `900` · `1800` · `3600` | — | Bar duration in seconds: from 1 second (`1`) to 1 hour (`3600`). | | `weeks` | integer | `1` | 0 to 12 | — | Number of weeks published, current week included. `days`, `weeks` and `months` cannot all be 0. | ## Objects received Each object keeps the same `id` from one update to the next. Its data is in the `data` field. Prices are in ticks: multiply them by the instrument’s tick size (`GET /v1/instruments`) to get points. ### `level` (sent in progress) Level; in progress during the current period, final once it ends, removed when the period leaves the window. With a count of 1, the level is removed without ever being final. `id` format: `::