CrossHair documentation
A menu-bar utility for picking pixels and laying out interfaces. Four overlays — crosshair, loupe, guides, measure — each one keystroke away. This page walks through how to use them.
Installation
CrossHair comes three ways. The download from bendansby.com/apps/crosshair is a standard .dmg — open it and drag CrossHair.app to your Applications folder. The Mac App Store version installs and updates the usual way. The Setapp version lives at setapp.com/apps/crosshair and installs through the Setapp client; no separate license key, no trial.
Requires macOS 14 Sonoma or later, on Apple Silicon or Intel. The direct-download build auto-updates via Sparkle; you can also check anytime via Preferences → Check for Updates…. The Mac App Store and Setapp builds update through their own channels. See License for the differences between the three.
Screen Recording
CrossHair asks for Screen Recording permission on first launch. It needs it for the loupe to magnify the pixels under your cursor, for the crosshair to read the background to stay legible, and for Measure to auto-fit its dimension lines to colour edges in the UI underneath.
Nothing is recorded, saved, or sent anywhere. CrossHair reads pixels live and forgets every frame the moment the next one arrives.
The menu bar item
CrossHair lives in the menu bar (the little crosshair glyph). Click it to open a menu with each overlay, Preferences, and Quit. You can hide the icon entirely in Preferences → Menu Bar → Show icon in menu bar — once it's hidden, re-open CrossHair from Finder to get back to Preferences.
The click action of the icon is configurable. By default a primary click opens the menu; you can switch it to summon one of the overlays directly (see Click action). A right-click always opens the menu so Preferences and Quit stay reachable.
Crosshair
Press ⌘⌥X for a fullscreen transparent overlay with a crosshair that follows your mouse. Esc dismisses.
The crosshair is drawn as a two-pass stroke — dark first, white on top, both at 55% — so it reads on any background. On a light surface the dark pass wins; on a dark surface the white pass wins; on a midtone background both are visible.
Arrow keys nudge the system cursor by one point per press, ten with ⇧. Useful for landing the cursor on a pixel exactly when the mouse is too sloppy.
Loupe
Press ⌘⌥L for a circular zoomed view of the screen pixels under your cursor. A hint pill below the glass lists the controls.
| Keys | Action |
|---|---|
| 1 / 2 | Shrink / grow the loupe |
| ‹ / › or − / + | Zoom out / in |
| P | Toggle the pixel grid (one cell per source pixel) |
| G | Drop a horizontal + vertical guide pair at the reticle |
| F | Cycle the colour readout — Hex → RGB → HSL → CMYK |
| C | Copy the colour under the reticle, in whichever format is currently showing |
| ← / → / ↑ / ↓ | Walk the reticle one source pixel |
| Esc | Dismiss |
The reticle walks independently of the system cursor — arrow presses advance it one source pixel at a time inside the glass, even though the cursor (and the captured sample around it) stays put. The reticle eases back to centre the moment you move the mouse.
The footer readout under the glass shows the sampled colour in whatever format you last picked with F — Hex, RGB, HSL, or CMYK — and C always copies exactly what's on screen, so switching formats and copying stays a two-key move.
Guides
Press ⌘⌥G for a transparent fullscreen overlay you can use to drop horizontal and vertical alignment lines anywhere on screen. Guides persist across launches.
A small HUD chip at the top of the screen offers:
| Button | Action |
|---|---|
| + H / + V | Arm a placement tool — click repeatedly to drop as many lines as you like, without re-arming between drops |
| Clear | Delete every guide (undoable) |
| Confirm | Lock the overlay click-through so lines stay visible while every click goes to the app underneath |
+ H / + V are toggles, not one-shot buttons — click once and the tool stays armed for repeated drops until you click it again, press Esc, or leave edit mode. A fresh Add Guides session starts pre-armed in + V mode, so the first click drops a guide immediately. H / V arm the same two tools straight from the keyboard — press the one that's already armed to disarm it, or press the other to switch directly, no need to disarm first.
While the overlay is in edit mode:
- Drag any guide to reposition.
- Click to select; ⌫ removes the selected guide.
- Arrow keys nudge along the guide's axis — one point per press, ten with ⇧.
- C is the keyboard shortcut for Clear; Return is Confirm (alongside Esc to dismiss).
- ⌘Z / ⌘⇧Z undo / redo creates and deletes.
- Hovering an existing guide, or watching the ghost line while a placement tool is armed, shows a small pill with its exact coordinate —
Y: 428for a horizontal guide,X: 210for a vertical one.
Pressing ⌘⌥G again toggles between edit and lock modes. To dismiss the overlay entirely — without losing your guides — use Hide Guides from the menu bar or the × button on the HUD.
Drop guides from the loupe
While the loupe is up, press G to lay a horizontal + vertical guide pair right at the reticle. Pinpoint a pixel at magnification, then mark it in one keystroke. The guides shoot out from the reticle with the same laser-line flash as the Guides overlay's HUD.
Measure
Press ⌘⌥M for a transparent overlay that lays measurement lines over anything on screen.
Drag for a free measurement
Drag out a line — the length is shown live in points. Hover the line or its pill to flip to pixels. Drag the end caps to adjust, drag the line to reposition, arrow keys nudge the selected handle, ⌫ removes.
Click for an auto-fit cross
Click once in a flat-colour region and Measure drops an auto-fit cross that snaps to the full width and height of that colour band — perfect for measuring a button, a sidebar, a padding gap. A faint dashed preview shows what a click will produce while you hover, with live width / height labels so you can read the dimensions of every flat-colour band as you sweep the cursor around — no need to commit a measurement just to check.
Point to Point, for angled measurements
Switch the HUD toggle to Point to Point, then click two spots to draw a line at any angle — not just horizontal or vertical. A hint pill appears while the tool is armed and waiting for its first click. Hold ⇧ while placing or resizing the second point to snap the line to the nearest 45°.
Snapping to guides
Manual measurements snap to any guides on screen while you drag or resize them, so a measurement lines up exactly with a guide-marked edge. Hold ⌥ during the drag to disable snapping for that one move.
Hold ⌥ for pixels
Holding the Option key — when not mid-drag — flips every label in the overlay — the ghost preview plus every committed measurement — from points to pixels in one keystroke. Release to flip back. Hover still works the per-measurement way; ⌥ is the global swap when you want all of them at once.
HUD
The top HUD chip offers an Auto / Point to Point toggle for the click behaviour, followed by the action buttons:
| Button | Action |
|---|---|
| Auto / Point to Point | Switch between auto-fit crosses (drag/click) and two-click angled lines |
| Clear | Delete every measurement (undoable) |
| Confirm | Lock the overlay click-through so measurements stay on screen while you keep working |
Same keyboard polish as Guides — C clears, Return confirms, Esc dismisses, ⌘Z / ⌘⇧Z undo / redo.
Shortcuts
Preferences → Keyboard Shortcuts lets you rebind every overlay's hotkey. Each shortcut needs at least one modifier (⌃ ⌥ ⇧ ⌘). A small Reset chip appears next to any row that's been changed from the default.
You can also clear a shortcut entirely to disable it — a valid state for menu-bar-only use, or if you only want one overlay reachable from the icon.
Click action
Preferences → Menu Bar → Clicking the icon sets what a primary click of the menu-bar icon does:
- Opens the menu — classic behaviour. The full menu drops down.
- Shows the crosshair / Shows the loupe / Shows the guides / Shows measure — primary click summons that overlay directly.
Right-click the icon always opens the menu, so Preferences and Quit stay reachable regardless of the click action you pick.
Open at login
Preferences → General → Open at login launches CrossHair quietly when you log in. The system's own registration is the source of truth — you can also flip this from System Settings → General → Login Items without going through CrossHair.
Keyboard shortcuts
| Keys | Action |
|---|---|
| ⌘⌥X | Show / hide the crosshair |
| ⌘⌥L | Show / hide the loupe |
| ⌘⌥G | Show / cycle the guides overlay |
| ⌘⌥M | Show / cycle Measure |
| Esc | Dismiss the active overlay |
| ← / → / ↑ / ↓ | Nudge cursor (crosshair) or reticle (loupe) one point / pixel |
| ⇧-arrow | Nudge ten at a time |
| 1 / 2 | Shrink / grow the loupe |
| ‹ / › or − / + | Loupe zoom out / in |
| P | Toggle the loupe pixel grid |
| G | Drop guides at the loupe reticle |
| F | Cycle the loupe colour format (Hex / RGB / HSL / CMYK) |
| C | Copy the loupe colour, or Clear in Guides / Measure edit mode |
| H / V | Arm the + H / + V guide-placement tools (Guides edit mode) |
| ⇧ while placing a Point to Point measurement | Snap the line to the nearest 45° |
| ⌥ while dragging a measurement | Disable guide snapping for that drag |
| Return | Confirm (Guides / Measure edit mode) |
| ⌘Z / ⌘⇧Z | Undo / Redo (Guides / Measure) |
| ⌫ | Delete the selected guide / measurement |
Accessibility
CrossHair honours macOS accessibility settings:
- VoiceOver + Voice Control. Preferences, the welcome window, the status menu, and every dialog use standard AppKit / SwiftUI controls with their labels intact.
- Dark Interface. Every surface adapts to the system appearance; overlays draw two-pass strokes that read on any background.
- Reduce Motion. The guide-drop laser flash and the measure auto-fit shake are skipped — guides and measurements appear at their final position instantly.
- Differentiate Without Color. No state is encoded by colour alone. Permissions show a check glyph + text; menu items pair SF Symbols with labels; selection in Measure uses colour and visible handles together.
Languages
CrossHair is localized into English, Deutsch, Español, Français, Italiano, 日本語, 한국어, Português (Brasil), Українська, Русский, and 简体中文. It picks the right language automatically based on your System Settings → General → Language & Region preferences.
To pin CrossHair to a specific language without changing system preferences, open System Settings → General → Language & Region → Applications, click the + button, and pick CrossHair.
License
CrossHair ships through three channels — pick the one that fits how you like to pay for software:
- Direct download. 7-day free trial with every feature unlocked, no watermark, no reminders. A one-time license then unlocks unlimited use. Buy via Buy License… in the menu bar; activate via Enter License…. Activation needs the internet briefly, then works offline; CrossHair revalidates quietly in the background so refunded or revoked keys stop working. After the trial ends (and only until a license is entered), an unlicensed copy shows a brief one-screen reminder every tenth time you summon an overlay — no feature is locked.
- Mac App Store. Paid through Apple's standard pipeline — buy it once, no separate license key, no trial.
- Setapp. Subscribe to CrossHair directly at setapp.com/apps/crosshair. No separate license key; Setapp delivers updates automatically.