Decision guide
Best format for long-term archives
Archival value comes from open specifications, lossless storage and active maintenance. The engine ranks every format in the graph on those dimensions, across all media types.
Short answer: CSV ranks first (100/100) because the specification is public, so a decoder can always be rebuilt.
The ranking, and the reasoning behind it
Scores are computed from structured facts in the knowledge graph, weighted for this specific question. Nothing here is written by hand, and every line of reasoning traces back to a recorded fact.
#1CSV
100/100
CSV is a plain-text table format that every spreadsheet and database can read.
All CSV factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly.
- Future-proofing 100/100 — it is actively maintained and current; open specifications outlive the companies that create them.
#2HTML
98/100
HTML is the markup language of the web, structuring text, media and links.
All HTML factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#3Markdown
98/100
Markdown is plain text with a light syntax that converts cleanly to HTML.
All Markdown factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#4ODT
98/100
ODT is the ISO-standard open document format used by LibreOffice.
All ODT factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#5PDF
98/100
PDF is the fixed-layout document format that renders identically everywhere.
All PDF factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly; an official specification document is publicly reachable.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#6PNG
98/100
PNG is a lossless raster format with full alpha transparency, built for graphics.
All PNG factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly; an official specification document is publicly reachable.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#7SVG
98/100
SVG is an XML vector format that stays sharp at any size.
All SVG factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly; an official specification document is publicly reachable.
- Licensing 100/100 — an openly specified format can be implemented without a licence negotiation; the core patents are old enough to have expired.
#8DOCX
97/100
DOCX is Microsoft Word's ZIP-packaged XML document format.
All DOCX factsWhy it scores well
- Long-term archiving 100/100 — the specification is public, so a decoder can always be rebuilt; lossless storage preserves the original data for future migrations.
- Open standards 100/100 — the specification is published openly.
- Future-proofing 100/100 — it is actively maintained and current; open specifications outlive the companies that create them.
How this ranking is calculated
Each format is scored 0–100 on every dimension the graph can evaluate for it. For this question the dimensions carry these weights:
- archiving ×3
- open standards ×3
- future proofing ×2
- licensing ×1
- popularity ×1
No machine learning is involved. The engine is deterministic: the same facts always produce the same ranking, and adding a new fact to the graph updates it automatically.
Frequently asked questions
Why do archives prefer open formats?
- Because a published specification means a decoder can always be rebuilt, even if every vendor that shipped one disappears.