Last updated ·Published ·By the WiserWork team
Free US Reference & Lookup Tools
6 quick lookups for ZIP codes, area codes, holidays and US data
Some questions just need a fast, clean answer: which city is this ZIP code, whose area code keeps calling, is the market open Monday or is it a federal holiday, when exactly does daylight saving change. Each tool here answers one of those in a single input, without the ad-maze most lookup sites put between you and the answer.
Most lookups run from data built into the page itself, so they work instantly and privately. The ZIP code tool queries a public geographic API (the only tool in this set that calls out, and only with the ZIP you type — see each tool's privacy note). Reference tables like gas-price averages state their data vintage clearly so you know exactly what you're looking at.
All US Info Tools at a Glance
What Each Tool Does
Every tool below opens instantly, needs no account, and processes your data locally in your browser. Here is what each one is for:
ZIP Lookup
Live ZIP-to-city/state/coordinates lookup, and the anatomy of the ZIP system — first-digit zones, prefixes, ZIP+4 and the codes that cross state lines. Open the ZIP Lookup →
Area Codes
Both-direction lookup across all US geographic area codes — code to state or state to codes — with the overlay era and scam-call caveats explained. Open the Area Codes →
Federal Holidays
The 11 federal holidays computed for any year — floating-Monday rules, weekend observance shifts, long-weekend flags, and the banks/markets/mail closure grid. Open the Federal Holidays →
Gas by State
All 50 states' typical price levels with the tax/refinery anatomy of the spread, plus the fill-up-across-the-border savings math. Open the Gas by State →
DST Adjuster
Transition dates computed through 2030, the AZ/HI exceptions, your device's live offset, and why November meetings with Phoenix move an hour. Open the DST Adjuster →
Leap Year
The full divisible-by-4/100/400 rule applied to any year, the next-leap-years list, and the Feb 29 legal quirks (licenses, birthdays, payroll). Open the Leap Year →
How to Choose the Right Tool
ZIP Code Lookup and Area Code Finder answer the two classic "where is this from?" questions — the ZIP tool geocodes live, the area-code tool works entirely offline from the embedded NANPA dataset. The Federal Holiday Calendar computes any year's official holidays (with observed dates for weekend holidays and what's closed). Gas Price by State benchmarks fuel costs for trip planning across state lines, and the DST Adjuster shows exactly which weekends the clocks change and how that shifts times against other countries.
Frequently Asked Questions
Where does the lookup data come from?
Area codes from the public NANPA numbering plan, holidays computed from the federal statute rules (5 U.S.C. 6103), gas prices from public EIA/AAA averages with the date stamped, and ZIP geocoding from the open Zippopotam.us API.
Do the lookup tools track what I search?
No. Searches run locally against embedded data; only the ZIP lookup sends the ZIP itself to the public geocoding API, and nothing is logged by WiserWork either way.
How current are the reference tables?
Each table shows its data vintage. Holiday and DST dates are computed (always current); average-price tables are refreshed with site updates.
Why is there no live election poll tracker?
Reliable poll aggregation requires licensed data feeds; a stale or unsourced tracker would be misleading. We chose not to ship one rather than ship a bad one.
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