Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width
Fletcher checksum over the input payload, in 16-bit (default) or 32-bit width. Returns the checksum as an unsigned integer and hex. Non-cryptographic.
Answeringour last check, 2026-09-24
1 of 1checks answered this week
446 msmedian answer time
$0.002listed price per call
$0.002price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://checksum.openverbs.com/v1/fletcher
| Category | Everything else |
|---|---|
| Provider host | checksum.openverbs.com |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 3 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-09-24 | valid payment request | 402 | $0.002 | 446 ms |
Example input (from the provider)
{
"body": {
"bits": 16,
"data": "example",
"encoding": "utf8"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"bits": {
"description": "Checksum width in bits. Default 16.",
"enum": [
16,
32
],
"type": "integer"
},
"data": {
"description": "Input payload.",
"maxLength": 5000000,
"type": "string"
},
"encoding": {
"description": "How to decode `data`. Default utf8.",
"enum": [
"utf8",
"hex",
"base64"
],
"type": "string"
}
},
"required": [
"data"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}