# PLANET
> Source: https://docs.barcoder.ai/docs/standards/planet
> research date 2026-06-03 · extracted at 2026-10-03
> Publisher: Barcoder — encyclopedia of QR, barcode and payment-code standards
Specifications:
- [Postal Alpha Numeric Encoding Technique — Wikipedia](https://en.wikipedia.org/wiki/Postal_Alpha_Numeric_Encoding_Technique)
- [PLANET Barcode — Neodynamic](https://www.neodynamic.com/Products/Help/BarcodeCF2.0/barcodes/Planet.htm)
## Overview
**PLANET** (**Postal Alpha Numeric Encoding Technique**) is a legacy, height-modulated barcode developed by the **United States Postal Service** to identify and track pieces of mail during delivery as part of the Post Office's **Confirm service** [1][1], [2][2]. It was the **tracking companion** to the routing-focused [POSTNET](https://docs.barcoder.ai/docs/standards/postnet) barcode, and its bar pattern is the **direct inverse** of POSTNET — where a POSTNET digit uses two tall and three short bars, the corresponding PLANET digit uses three tall and two short bars [1][1], [3][3], [4][4]. PLANET was **fully superseded by the [Intelligent Mail Barcode](https://docs.barcoder.ai/docs/standards/intelligent-mail-barcode) by January 28, 2013** [5][5], [4][4].
## History
- The PLANET barcode (Postal Alpha Numeric Encoding Technique) was developed by the **United States Postal Service** to identify and track pieces of mail during delivery — the Post Office's **Confirm services** [1][1].
- The [Intelligent Mail Barcode](https://docs.barcoder.ai/docs/standards/intelligent-mail-barcode) (IMb) replaced USPS PLANET in **2013** [4][4]; PLANET was **fully superseded by the IMb by January 28, 2013** [5][5].
*(Authoritative sources document PLANET's purpose and 2013 deprecation but do not give a reliable, consistent introduction year; that date is omitted rather than fabricated.)*
## Technical specification
PLANET is a **two-state, height-modulated 1D postal symbology**, structurally the inverse of [POSTNET](https://docs.barcoder.ai/docs/standards/postnet) [1][1], [2][2], [3][3]:
| Parameter | Value |
|---|---|
| Symbology family | 1D height-modulated, two-state (tall / short bars) |
| Length | 12 or 14 digits |
| Per-digit encoding | 5 bars, two-of-five code (3 tall + 2 short — inverse of POSTNET) |
| Framing | always starts and ends with a full (long) frame bar |
| Bar widths/spaces | all bars same width, all spaces same width; data carried by bar height |
| Check digit | modulo-10 (detection only) |
| Character set | numeric only |
**Digit encoding** — like POSTNET, PLANET uses half- and full-height bars with **five bars per digit in a two-of-five code**, but here **the two-of-five are the short bars** (i.e., three tall and two short), making each PLANET digit the height-inverse of the corresponding POSTNET digit [1][1], [3][3]. The symbol always begins and ends with a long framing bar [1][1], [3][3].
**Data structure (12-digit form)** [2][2]:
| Field | Length |
|---|---|
| Service type | 2 digits (e.g. 21 = Origin Confirm, 22 = Destination Confirm) |
| Mail-piece identification | 9 digits |
| Check digit | 1 digit |
**Check digit** — chosen as the single digit (0–9) that, when added to the sum of the other digits, makes the total a multiple of 10 [1][1], [3][3]. The check provides error *detection* only, with no correction [4][4].
## Use cases
- **USPS Confirm service mail tracking** — PLANET was developed to let mailers uniquely identify and track mail through the Postal Service's Confirm program [1][1], [3][3].
- **Origin and Destination Confirm** — two formats: **Destination Confirm** tracked outgoing mailings, and **Origin Confirm** tracked incoming (reply) mail [3][3].
- **Inbound and outbound letter-mail tracking** — PLANET barcodes complemented the routing-focused POSTNET barcodes on the same mailpiece, adding tracking visibility for both inbound and outbound letter mail [6][6].
- **Tracked attributes** — PLANET-based Confirm tracked mailpiece class, shape, subscriber identification, and custom information such as mailing numbers or campaign IDs [1][1].
## Implementations
- **C** — [zint/zint][7] — 771★, active 2026. Encoding library supporting PLANET among 50+ symbologies.
- **JavaScript** — [metafloor/bwip-js][8] — 2,381★, active 2026. Pure-JavaScript barcode writer supporting PLANET and POSTNET among 100+ types.
- **JavaScript decoder** — Douglas Boynton Quine publishes a browser-based POSTNET / PLANET / IMb decoder [5][5].
## Comparison
**vs. [POSTNET](https://docs.barcoder.ai/docs/standards/postnet)** — PLANET and POSTNET share the same two-state, height-modulated, two-of-five, modulo-10 framework but serve opposite purposes and are geometric inverses of each other: POSTNET encodes **routing** (ZIP) data with two tall + three short bars per digit, while PLANET encodes **tracking** data with three tall + two short bars per digit [1][1], [3][3], [4][4]. The two were commonly printed together on a single mailpiece.
**vs. [Intelligent Mail Barcode](https://docs.barcoder.ai/docs/standards/intelligent-mail-barcode)** — The IMb is a four-state symbology that merges PLANET's tracking data and POSTNET's routing data into one 65-bar symbol with an 11-bit CRC; PLANET is two-state, 12–14 digits, tracking-only, with a single modulo-10 check digit [4][4]. The IMb absorbed PLANET's Confirm-tracking role and superseded it on January 28, 2013 [4][4], [5][5].
**When to choose it** — for new mail, never: PLANET is a legacy barcode that should not be used; the Intelligent Mail Barcode is its replacement [4][4]. PLANET remains relevant only for reading or reproducing legacy Confirm-service mailpieces.
## Fun facts
- PLANET is one of the few barcode symbologies defined as the **exact height-inverse of another symbology** — flipping every POSTNET digit's tall and short bars produces the corresponding PLANET digit, a deliberate design so the routing and tracking codes were visually and structurally distinct on the same envelope [1][1], [4][4].
- Its acronym, **Postal Alpha Numeric Encoding Technique**, parallels POSTNET's **Postal Numeric Encoding Technique** — yet despite the "Alpha Numeric" name, PLANET encodes numeric data only [1][1].
## Status
**Deprecated / superseded.** PLANET was a legacy tracking barcode that should no longer be used; the [Intelligent Mail Barcode](https://docs.barcoder.ai/docs/standards/intelligent-mail-barcode) is its replacement [4][4]. The IMb replaced PLANET in **2013**, with full supersession by **January 28, 2013** [4][4], [5][5]. Its successor is the Intelligent Mail Barcode [4][4], [5][5].
## Sources
[1]: https://en.wikipedia.org/wiki/Postal_Alpha_Numeric_Encoding_Technique
[2]: https://www.neodynamic.com/Products/Help/BarcodeCF2.0/barcodes/Planet.htm
[3]: https://www.barcodefaq.com/usps-postal/
[4]: https://www.dynamsoft.com/blog/insights/intelligent-mail-vs-postnet-vs-planet/
[5]: https://www.quine.org/postnetj.html
[6]: https://www.scandit.com/products/barcode-scanning/symbologies/usps-intelligent-mail/
[7]: https://github.com/zint/zint
[8]: https://github.com/metafloor/bwip-js
[postnet]: https://docs.barcoder.ai/source/standards/postnet
[intelligent-mail-barcode]: https://docs.barcoder.ai/source/standards/intelligent-mail-barcode
1. [Postal Alpha Numeric Encoding Technique — Wikipedia][1] — Wikipedia, accessed 2026-06-03
2. [PLANET Barcode — Neodynamic][2] — Neodynamic, accessed 2026-06-03
3. [USPS Barcode FAQ & Tutorial — BarcodeFAQ.com][3] — BarcodeFAQ.com, accessed 2026-06-03
4. [Difference Between Intelligent Mail barcode, Postnet and Planet — Dynamsoft][4] — Dynamsoft, accessed 2026-06-03
5. [USPS POSTNET, PLANET, and IMB Barcode Decoder in JavaScript — Douglas Boynton Quine][5] — quine.org, accessed 2026-06-03
6. [USPS Intelligent Mail Barcode — Scandit][6] — Scandit, accessed 2026-06-03
## Deployments
_No country reports mention this standard by name._