JOSM can comfortably load 100MB of OSM XML data, but larger extracts will have severe performance issue.
A perhaps outdated list of default shortcuts; and Mapbox's list of shortcuts.
† denotes customized shortcuts.
C, search actions.
F3, preset list;
F11, fullscreen (toggle);
F12, preferences;
TAB, dialogs (toggle);
M⇧l, layers;
M⇧t, tags/memberships†;
M⇧s, selection†;
M⇧r, relations;
M⇧o, command stack;
M⇧f, filter;
M⇧m, map styles;
Cw, wireframe view (toggle);
+, zoom in about center of map view;
-, zoom out about center of map view;
C,, zoom in about mouse;
C., zoom out about mouse;
1, zoom to data;
2, zoom to layer;
3, zoom to selection;
C←↑→↓, move viewport;
RightMouse, drag to move viewport;
8, previous viewport;
9, next viewport;
s, select mode (rectangle / lasso);
Ca, select all;
Cf, search objects;
⇧F3, search objects by preset;
Del, delete selection.
a, draw mode (standard nodes and ways / snap to angle).
Modifiers:
C, disable snapping;
M, disable continuing;
⇧, disable auto-connect.
x, extrude mode (stretch / dual alignment).
Modifiers:
C, move along/parallel;
M, create new way;
⇧, always create nodes.
w, improve way accuracy mode.
C⇧, drag to rotate objects around their geometrical centre;
CM, drag to scale objects around their geometrical centre;
Cm, merge layers (downwards layer-by-layer);
C⇧m, merge selection;
Filter:
filter lines are evaluated from top down;
reverse filtering exclude every entity without a specific tag -highway:;
parts of a highway child (type:way & highway:);
only roads for public transport -((highway | child highway | untagged | public_transport) & -(highway=footway | highway=path | highway=steps | highway=track));
aggressive clean up natural: | waterway: | boundary: | landuse: | building: | leisure: | amenity:;
all natural and land use areas formed by relations child (type:relation & (natural:|landuse:));
disable tagless nodes type:node untagged;
using tag count to disable fully tagged objects;
disable/highlight recently modified objects to visualize progress new modified, (modified | user:CartoRD);
highlight stale data timestamp:2009-08-15/;
Map paint styles:
Address Validator for street addresses; Modified for modified objects;
Plugins:
CMt, Turn Restriction Editor 1-9;t;