# Add Singapore Official Working Days

> Adds or subtracts dates using Singapore's pinned national public-holiday dates and the CLDR Saturday/Sunday baseline.

- Calculator id: `singapore-add-working-days` · Category: Everyday Life (`everyday`) · Tool name: `add_singapore_working_days`
- Canonical page: https://tttkmbb.com/everyday/singapore-add-working-days · This document: https://tttkmbb.com/everyday/singapore-add-working-days.md · JSON definition: https://tttkmbb.com/everyday/singapore-add-working-days.json

## Purpose

Adds or subtracts dates using Singapore's pinned national public-holiday dates and the CLDR Saturday/Sunday baseline.

**Use when:** You need a deterministic Singapore date offset in 2026-2027 and accept the stated employer-rest-day limitation.

**Do not use when:** You need an employer-specific roster, bank/exchange calendar or a date outside 2026-2027.

## Example user requests

- Add five Singapore working days after 2027-02-05.


## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `start_date` | date |  | required | Gregorian start date in 2026-2027. |
| `working_days` | integer |  | required | Signed offset; start date is excluded for non-zero offsets. (min -1000, max 1000) |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `start_date` | date |  | Input date. |
| `result_date` | date |  | Date reached. |
| `working_days_added` | integer |  | Signed requested offset. |
| `calendar_days_elapsed` | integer |  | Signed Gregorian difference. |
| `public_holidays_skipped` | list |  | MOM holidays crossed. |
| `territory` | string |  | SG. |
| `territory_name` | string |  | Singapore. |
| `day_type` | string |  | Regular weekday, regular weekend or MOM public holiday. |
| `holiday_names` | string_list |  | MOM holiday names applying on the date. |
| `holiday_observed` | boolean |  | True when the source explicitly publishes an observed date. |
| `weekend_days` | string_list |  | CLDR weekend convention used only as the baseline. |
| `rest_day_policy` | string |  | Employer-specific weekly rest-day placement is not inferred. |
| `calendar_scope` | string |  | Singapore national public holidays plus the CLDR Saturday/Sunday baseline. |
| `calendar_profile` | string |  | singapore-mom-public-holidays. |
| `source_quality` | string |  | Official Singapore government sources, with employer-rest-day limitation. |
| `dataset_version` | string |  | Pinned MOM evidence package. |
| `sources` | list |  | Official MOM, government open-data and legislation sources. |

## Formula

`move one day at a time; decrement remaining only when Singapore status.is_working_day=true`

Skip CLDR weekend dates and pinned MOM public-holiday dates; do not infer employer rest-day substitutions.

## Data Sources

- Singapore Ministry of Manpower Public Holidays for 2026 — https://www.mom.gov.sg/newsroom/press-releases/2025/0616-public-holidays-for-2026 (government, published 2025-06-16)
- Singapore Ministry of Manpower Public Holidays for 2027 — https://www.mom.gov.sg/newsroom/press-releases/2026/0618-public-holidays-for-2027 (government, published 2026-06-18)
- Singapore public holidays 2027 open-data mirror — https://data.gov.sg/datasets/d_0ba69fc6d56717ff0bf8083c6af3bb84/view (government_open_data, published 2026-07-03)
- Singapore Holidays Act 1998 — https://sso.agc.gov.sg/Act/HA1998 (legislation)

Data freshness: `static`. Pinned MOM 2026-2027 package.

## API

- `GET https://tttkmbb.com/api/v1/calculate/singapore-add-working-days?start_date=…&working_days=…`
- `POST https://tttkmbb.com/api/v1/calculate/singapore-add-working-days` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/singapore-add-working-days · OpenAPI operationId `add_singapore_working_days` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool: `add_singapore_working_days` (dedicated) or `run_calculator` with `{"calculator_id": "singapore-add-working-days", "inputs": {…}}`

## Example

- Offset across Chinese New Year: inputs `{"start_date":"2027-02-05","working_days":5}` → `{"result_date":"2027-02-15"}`

```
GET https://tttkmbb.com/api/v1/calculate/singapore-add-working-days?start_date=2027-02-05&working_days=5
```

## Limitations

You need an employer-specific roster, bank/exchange calendar or a date outside 2026-2027. Skip CLDR weekend dates and pinned MOM public-holiday dates; do not infer employer rest-day substitutions. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**Are employer rest days included?**

No. Only the public-holiday package and weekly baseline are used.

## Related

- [Singapore Official Public-Holiday Working Day](https://tttkmbb.com/everyday/singapore-working-day.md) — Inspect one date and its official sources.