Why Spoold Is the Best Developer Utility — 72+ Tools & Features Only Here
Spoold is a free, privacy-first developer toolbox with Magic Box paste detection, curl Compare, CSV/JSON query tools, an LLM toolkit, S3/R2 CORS debugger, and 72+ browser tools that work together — no sign-up required.
One toolbox. Paste once. Ship faster.
72+ browser tools that share paste detection, cross-tool handoff, and workflows you won't find bundled anywhere else.
Open Magic Box →Browse all tools →
Only at Spoold
Individual tools exist elsewhere. These workflows are wired together here.
Magic Box
Paste anything — JSON, curl, JWT, CSV, Base64, gzip — auto-detect format and jump to the right tool.
Open tool →curl Compare
Structural diff of two curl commands: URL, headers, auth, cookies, body — not a text dump.
Open tool →CSV & JSON Operations
Query pasted data with where(), unique(), compare(), countBy() — no Python, jq, or upload.
Open tool →curl Online + Viewer
Paste, inspect, edit, and send HTTP requests. Pair with Compare for staging vs prod debugging.
Open tool →OpenAPI → curl
Browse a Swagger spec, pick an endpoint, generate a curl — send or compare in one flow.
Open tool →LLM toolkit
Token counter, vision tokens, context budget, RAM estimator, and stream log viewer — one suite.
Open tool →S3 / R2 CORS debugger
Generate CORS policies and debug preflight failures for browser uploads to S3 or Cloudflare R2.
Open tool →Regex Generator
Give sample strings or a log file — get capture-group patterns, refine and test inline.
Open tool →Cross-tool handoff
Magic Box stash + Next Tools suggestions carry your data between steps without re-pasting.
Open tool →Spoold vs typical tool sites
| Need | Typical site | Spoold |
|---|---|---|
| Auto-detect pasted format | Pick tool first | Magic Box |
| Diff two curls | Text compare | curl Compare |
| Query CSV data | Convert only | CSV Operations |
| LLM dev utilities | One token counter | LLM toolkit |
| Fix S3/R2 CORS | Docs + guesswork | CORS debugger |
| Chain tools together | Copy between tabs | Handoff + Next Tools |
| Account | Often required | None |
Popular workflows
🔄 API debugging
📦 Data wrangling
- Paste CSV or upload
.xlsx where()·unique()·dedupe()- Export or hand off to JSON formatter
🤖 LLM building
- Count tokens with tiktoken
- Split context window
- Parse SSE stream logs
☁️ Object storage
- Browser upload fails with CORS error
- Generate policy for S3 or R2
- Debug preflight, fix, retry
LLM toolkit at a glance
72+ tools, six categories
Data
JSON, CSV, YAML, SQL
Web & API
curl, OpenAPI, CORS
Security
JWT, TLS chains
Encode
Base64, hex, gzip
LLM
Tokens, vision, streams
Text
Diff, regex, Mermaid
🔒 Privacy-first
FAQ
Is Spoold free?
What makes it different from a JSON formatter site?
Does it upload my data?
Most unique feature?
How do I start?
Try it now
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