Fix NaN/Infinity in JSON (no upload)
JSON does not support NaN/Infinity. Use null or strings and validate locally before exporting.
NaN/Infinity is not valid JSON: strict JSON validation vs lenient JSON repair
A practical alternative for NaN/Infinity is not valid JSON: trade-offs between strict JSON validation and lenient JSON repair, plus actionable next steps.
TL;DR: Start strict on a sample, apply minimal fixes, then scale only after validation passes.
Decision matrix
| Criteria | strict JSON validation | lenient JSON repair |
|---|---|---|
| Best when | You need strict, repeatable output | You need rapid triage on messy input |
| Risk profile | Lower hidden-issue risk, more upfront checks | Higher hidden-issue risk, faster initial pass |
| Typical speed | Slower first pass, faster downstream debugging | Faster first pass, may need rework later |
| Good for | Stable JSON pipelines | One-off fixes and incoming unknown formats |
| Avoid if | Input is heavily malformed and urgent turnaround is required | You need audit-grade guarantees |
Choose strict JSON validation when
- You need deterministic results for repeated JSON runs.
- You are fixing production data where hidden breakage is costly.
- You want clear pass/fail criteria before conversion or export.
Choose lenient JSON repair when
- You are in early triage and need to narrow the problem quickly.
- You are dealing with mixed-quality inbound files from multiple sources.
- You need an iterative cleanup loop before strict validation.
Recommended no-upload workflow
- Validate a representative sample first. Confirm exact error class/position.
- Pick workflow A or B. Use strict path for quality, flexible path for triage.
- Apply the smallest safe fix. Avoid broad rewrites before validation is green.
- Re-validate and convert/export. Only then run batch processing.
Recommended tools
Relevant guides
Auto-selected from existing guides for this topic. Need more: search by keyword.
System.Text.Json.JsonException: 'N' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.: what it means and how to fix it
Newtonsoft.Json error ('N' is an invalid start of a value. LineNumber: 0 | ByteP...): common causes (HTML instead of JSON, extra chars) and a safe no-upload validation workflow.
System.Text.Json.JsonException: 'I' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.: what it means and how to fix it
Newtonsoft.Json error ('I' is an invalid start of a value. LineNumber: 0 | ByteP...): common causes (HTML instead of JSON, extra chars) and a safe no-upload validation workflow.
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Related actions
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Related alternatives
- NDJSON/JSONL vs JSON
- Newlines in JSON strings
- Pretty vs minified JSON (debug faster)
- Missing quotes around JSON keys/strings
- Missing colon after JSON key
- JSON to XML: safe no-upload workflow
Related by intent
- Intent hub for NaN/Infinity is not valid JSON
- Execution playbook
- Method comparison
- Alternative flows
- Migration path
- Benchmark baseline
- Case study
- Trend report
- Cluster pillar
- Cross-cluster pillar: CSV
- Linkable data asset
Expert signal
Expert note: NaN/Infinity is not valid JSON usually resolves fastest when triage starts from strict validation and then branches to comparison/alternative paths based on input quality.
Data snapshot 2026
| Metric | Value |
|---|---|
| Intent confidence score | 94/100 |
| Predicted CTR uplift potential | 28% |
| Target crawl depth | < 3 clicks |
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