> ## Documentation Index
> Fetch the complete documentation index at: https://docs.maesn.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Standardized Data

> Technical explanation of standardized values used across all accounting integrations.

## ISO standardization

Maesn enforces international standards for all input and output data to ensure consistency.
All formats follow specifications published by the **International Organization for Standardization (ISO)**.
Any value not conforming to these standards may be rejected by the API.

### Country codes

Maesn uses **ISO 3166-1 alpha-2** country codes (two-letter uppercase).
These codes are required anywhere a country is referenced in the API.

**Supported Country Codes:**

<Accordion title="View all supported countries (249 codes)">
  `AD`, `AE`, `AF`, `AG`, `AI`, `AL`, `AM`, `AO`, `AQ`, `AR`, `AS`, `AT`, `AU`, `AW`, `AX`, `AZ`, `BA`, `BB`, `BD`, `BE`, `BF`, `BG`, `BH`, `BI`, `BJ`, `BL`, `BM`, `BN`, `BO`, `BQ`, `BR`, `BS`, `BT`, `BV`, `BW`, `BY`, `BZ`, `CA`, `CC`, `CD`, `CF`, `CG`, `CH`, `CI`, `CK`, `CL`, `CM`, `CN`, `CO`, `CR`, `CU`, `CV`, `CW`, `CX`, `CY`, `CZ`, `DE`, `DJ`, `DK`, `DM`, `DO`, `DZ`, `EC`, `EE`, `EG`, `EH`, `ER`, `ES`, `ET`, `FI`, `FJ`, `FK`, `FM`, `FO`, `FR`, `GA`, `GB`, `GD`, `GE`, `GF`, `GG`, `GH`, `GI`, `GL`, `GM`, `GN`, `GP`, `GQ`, `GR`, `GS`, `GT`, `GU`, `GW`, `GY`, `HK`, `HM`, `HN`, `HR`, `HT`, `HU`, `ID`, `IE`, `IL`, `IM`, `IN`, `IO`, `IQ`, `IR`, `IS`, `IT`, `JE`, `JM`, `JO`, `JP`, `KE`, `KG`, `KH`, `KI`, `KM`, `KN`, `KP`, `KR`, `KW`, `KY`, `KZ`, `LA`, `LB`, `LC`, `LI`, `LK`, `LR`, `LS`, `LT`, `LU`, `LV`, `LY`, `MA`, `MC`, `MD`, `ME`, `MF`, `MG`, `MH`, `MK`, `ML`, `MM`, `MN`, `MO`, `MP`, `MQ`, `MR`, `MS`, `MT`, `MU`, `MV`, `MW`, `MX`, `MY`, `MZ`, `NA`, `NC`, `NE`, `NF`, `NG`, `NI`, `NL`, `NO`, `NP`, `NR`, `NU`, `NZ`, `OM`, `PA`, `PE`, `PF`, `PG`, `PH`, `PK`, `PL`, `PM`, `PN`, `PR`, `PT`, `PW`, `PY`, `QA`, `RE`, `RO`, `RS`, `RU`, `RW`, `SA`, `SB`, `SC`, `SD`, `SE`, `SG`, `SH`, `SI`, `SJ`, `SK`, `SL`, `SM`, `SN`, `SO`, `SR`, `SS`, `ST`, `SV`, `SX`, `SY`, `SZ`, `TC`, `TD`, `TF`, `TG`, `TH`, `TJ`, `TK`, `TL`, `TM`, `TN`, `TO`, `TR`, `TT`, `TV`, `TW`, `TZ`, `UA`, `UG`, `UM`, `US`, `UY`, `UZ`, `VA`, `VC`, `VE`, `VG`, `VI`, `VN`, `VU`, `WF`, `WS`, `YE`, `YT`, `ZA`, `ZM`, `ZW`
</Accordion>

### Dates and Timestamps

All date and datetime fields in the Maesn API use ISO 8601 format. The two formats we allow are:

1. Date without timestamp:

```json theme={null}
2026-01-01
```

2. Date with UTC timestamp:

```json theme={null}
2026-01-01T14:15:06Z
```

We do not allow any other formats, such as dates with timezone offsets like `2026-01-01T14:15:06+02:00`.

This applies to all places where dates are used:

* Filters such as `lastModifiedAt`
* Fields like `createdDate` and `updatedDate`
* Any other date or datetime value

As all our supported systems handle dates in different ways, these are the two automatic conversions that will be applied if the date format doesn't match the system requirements:

1. **Date → DateTime Conversion**

If you send a date without a timestamp (e.g., `2026-01-01`), and the system or field requires a timestamp (for example, `lastModifiedAt` often requires timestamps), we will add midnight UTC to that date. The result will be `2026-01-01T00:00:00Z`.

2. **DateTime → Date Conversion**

If you send a timestamp (e.g., `2026-01-01T00:00:00Z`), and the system or field does not support timestamps (for example, `dueDate` seldom supports timestamps), we will simply exclude the timestamp and use the date only. The result will be `2026-01-01`.

### Currencies

Currencies are always represented using ISO 4217 three-letter currency codes (uppercase).

**Supported Currencies**

<Accordion title="View all supported currencies (150+ codes)">
  `AED`, `AFN`, `ALL`, `AMD`, `ANG`, `AOA`, `ARS`, `AUD`, `AWG`, `AZN`, `BAM`, `BBD`, `BDT`, `BGN`, `BHD`, `BIF`, `BMD`, `BND`, `BOB`, `BRL`, `BSD`, `BTN`, `BWP`, `BYR`, `BZD`, `CAD`, `CDF`, `CHF`, `CLP`, `CNY`, `COP`, `CRC`, `CUC`, `CVE`, `CZK`, `DJF`, `DKK`, `DOP`, `DZD`, `EEK`, `EGP`, `ERN`, `ETB`, `EUR`, `FJD`, `FKP`, `GBP`, `GEL`, `GHS`, `GIP`, `GMD`, `GNF`, `GQE`, `GTQ`, `GYD`, `HKD`, `HNL`, `HRK`, `HTG`, `HUF`, `IDR`, `ILS`, `INR`, `IQD`, `IRR`, `ISK`, `JMD`, `JOD`, `JPY`, `KES`, `KGS`, `KHR`, `KMF`, `KPW`, `KRW`, `KWD`, `KYD`, `KZT`, `LAK`, `LBP`, `LKR`, `LRD`, `LSL`, `LTL`, `LVL`, `LYD`, `MAD`, `MDL`, `MGA`, `MKD`, `MMK`, `MNT`, `MOP`, `MRO`, `MUR`, `MVR`, `MWK`, `MXN`, `MYR`, `MZM`, `NAD`, `NGN`, `NIO`, `NOK`, `NPR`, `NZD`, `OMR`, `PAB`, `PEN`, `PGK`, `PHP`, `PKR`, `PLN`, `PYG`, `QAR`, `RON`, `RSD`, `RUB`, `SAR`, `SBD`, `SCR`, `SDG`, `SEK`, `SGD`, `SHP`, `SLL`, `SOS`, `SRD`, `SYP`, `SZL`, `THB`, `TJS`, `TMT`, `TND`, `TRY`, `TTD`, `TWD`, `TZS`, `UAH`, `UGX`, `USD`, `UYU`, `UZS`, `VEB`, `VND`, `VUV`, `WST`, `XAF`, `XCD`, `XDR`, `XOF`, `XPF`, `YER`, `ZAR`, `ZMK`, `ZWR`
</Accordion>