These are actual METRO codes (legally binding laws)
(we added the bold to highlight regional centers)

Find your neighborhood  in METRO's definitions below  (we added the links to plain english definitions) --  then look up METRO's target density on the right

Metro Density Recommendations
Note that these are recommendations not mandates. Mandates are here.

For each of the following 2040 Growth Concept design types, city and county comprehensive plans shall be amended to include the boundaries of each area, determined by the city or county consistent with the general locations shown on the 2040 Growth Concept Map:

Central City --Downtown Portland is the Central City which serves as the major regional center, an employment and cultural center for the metropolitan area.

Regional Centers --Nine regional centers will become the focus of compact development, redevelopment and high-quality transit service and multimodal street networks.

Station Communities --Nodes of development centered approximately one-half mile around a light rail or high capacity transit station that feature a high-quality pedestrian environment.

Town Centers --Local retail and services will be provided in town centers with compact development and transit service.

Main Streets --Neighborhoods will be served by main streets with retail and service developments served by transit.

Corridors --Along good quality transit lines, corridors feature a high-quality pedestrian environment, convenient access to transit, and somewhat higher than current densities.

Employment Areas --Various types of employment and some residential development are encouraged in employment areas with limited commercial uses.

Industrial Areas -Industrial area are set aside primarily for industrial activities with limited supporting uses.

Inner Neighborhoods --Residential areas accessible to jobs and neighborhood businesses with smaller lot sizes are inner neighborhoods.

Outer Neighborhoods --Residential neighborhoods farther away from large employment centers with larger lot sizes and lower densities are outer neighborhoods.

(Ordinance No. 97-715B, Sec. 1.)

A. For the area of each of the 2040 Growth Concept design types, the following average densities for housing and employment are recommended to cities and counties:
Central City - 250 persons per acre
Regional Centers - 60 persons per acre
Station Communities - 45 persons per acre
Town Centers - 40 persons per acre
Main Streets - 39 persons per acre
Corridor - 25 persons per acre
Employment Areas - 20 persons per acre
Industrial Areas - 9 employees per acre
Inner Neighborhoods - 14 persons per acre
Outer Neighborhoods - 13 persons per acre

(Ordinance No. 97-715B, Sec. 1.)

Densities when Metro started (see Metro source document, below) Central City - 166 persons per acre Regional Centers - 24.6 persons per acre Station Communities - 11.4 persons per acre (these were just neighborhoods) Town Centers - 28.5 persons per acre Main Streets - 32 persons per acre Corridor - 19 persons per acre Employment Areas - 14.4 persons per acre Industrial Areas - unknown Inner Neighborhoods - 11.4 persons per acre Outer Neighborhoods - 8.6 persons per acre

This is the source of density before Metro. Use 1992 column.

Click on table for whole page and source information.

Metro codes from the Metro code at  http://www.multnomah.lib.or.us/metro/glance/metcode/metcode307.pdf