Source: https://guthlabs.ai/docs/instruments/base-encoding-size-calculator-text-data-bloat/implementation/

instrument implementation / implementation-contract

# Base Encoding Size Calculator (Text/Data Bloat) implementation

A source-bound implementation contract for Base Encoding Size Calculator (Text/Data Bloat); deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-026

**Effect**: Computation or source lookup only

## Input and validation requirements

Zero-byte input produces an undefined overhead percentage, and URL-encoding output depends on an unstated reserved-character convention. The calculator also has no safe numeric behavior for extreme magnitudes: for raw_byte_size = 1.7e308, the Base64 estimate 4 * ceil(1.7e308/3) is approximately 2.2666666666666668e308, which overflows JavaScript Number to Infinity; the input should be rejected as non-integral and out of range.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "raw_byte_size": 1,
    "encoding_scheme": "Base64"
  },
  "expected_outputs": {
    "encoded_size_bytes": 4,
    "overhead_percent": 300
  },
  "working": "1. Number of Base64 groups = ceil(1 / 3) = 1. 2. Each group produces 4 output bytes. 3. Encoded size = 4 × 1 = 4 bytes. 4. Overhead = (4 - 1) / 1 × 100 = 300%. Padding is included."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/base-encoding-size-calculator-text-data-bloat/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/base-encoding-size-calculator-text-data-bloat/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/base-encoding-size-calculator-text-data-bloat/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`