Fixed Format

Fixed format (also known as fixed-width) is a data interchange approach where every field has a predefined column width and is space-padded as needed. It contrasts with delimiter-separated formats like CSV, and is widely used in legacy mainframe systems, banking files, healthcare claims, government filings, and Unix system files such as /etc/passwd. While not an API in the REST sense, fixed-format files remain a critical data exchange medium that modern APIs and ETL pipelines must read and write.

Fixed Format is profiled on the APIs.io network. Tagged areas include Data Exchange, Data Formats, File Formats, Fixed Format, and Fixed Width.

📡 Source on GitHub

6.4/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

0 APIs

Data ExchangeData FormatsFile FormatsFixed FormatFixed WidthFlat FilesLegacy Systems Mainframe

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 6.4/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 1.4 / 20

Access Clarity 0.0 / 20

Operational Transparency 0.0 / 13

Contract Governance 0.0 / 12

Discoverability 5.0 / 10

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

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Resources

Documentation 1

Reference material describing how the API behaves

Reference

Reference

Source (apis.yml)

aid: fixed-format
name: Fixed Format
description: Fixed format (also known as fixed-width) is a data interchange approach where every field has a predefined column
  width and is space-padded as needed. It contrasts with delimiter-separated formats like CSV, and is widely used in legacy
  mainframe systems, banking files, healthcare claims, government filings, and Unix system files such as /etc/passwd. While
  not an API in the REST sense, fixed-format files remain a critical data exchange medium that modern APIs and ETL pipelines
  must read and write.
type: Index
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/fixed-format.png
url: https://raw.githubusercontent.com/api-evangelist/fixed-format/refs/heads/main/apis.yml
created: '2025-01-01'
modified: '2026-04-28'
specificationVersion: '0.23'
tags:
- Data Exchange
- Data Formats
- File Formats
- Fixed Format
- Fixed Width
- Flat Files
- Legacy Systems
- Mainframe
apis: []
common:
- type: Reference
  url: https://en.wikipedia.org/wiki/Flat-file_database
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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