> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getpara.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Verify Signatures with Cosmos Libraries

> Verify message and transaction signatures using CosmJS

export const Card = ({imgUrl, title, description, href, horizontal = false, newTab = false}) => {
  const [isHovered, setIsHovered] = useState(false);
  const handleClick = e => {
    e.preventDefault();
    if (newTab) {
      window.open(href, '_blank', 'noopener,noreferrer');
    } else {
      window.location.href = href;
    }
  };
  return <div className={`not-prose relative my-2 p-[1px] rounded-xl transition-all duration-300 ${isHovered ? 'bg-gradient-to-r from-[#FF4E00] to-[#874AE3]' : 'bg-gray-200'}`} onMouseEnter={() => setIsHovered(true)} onMouseLeave={() => setIsHovered(false)}>
      <a href={href} onClick={handleClick} className={`not-prose flex ${horizontal ? 'flex-row' : 'flex-col'} font-normal h-full bg-white overflow-hidden w-full cursor-pointer rounded-[11px] no-underline`}>
        {imgUrl && <div className={`relative overflow-hidden flex-shrink-0 ${horizontal ? 'w-[30%] rounded-l-[11px]' : 'w-full'}`} onClick={e => e.stopPropagation()}>
            <img src={imgUrl} alt={title} className="w-full h-full object-cover pointer-events-none select-none" draggable="false" />
            <div className="absolute inset-0 pointer-events-none" />
          </div>}
        <div className={`flex-grow px-6 py-5 ${horizontal ? 'w-[70%]' : 'w-full'} flex flex-col ${horizontal && imgUrl ? 'justify-center' : 'justify-start'}`}>
          {title && <h2 className="font-semibold text-base text-gray-800 m-0">{title}</h2>}
          {description && <div className={`font-normal text-gray-500 re leading-6 ${horizontal || !imgUrl ? 'mt-0' : 'mt-1'}`}>
              <p className="m-0 text-xs">{description}</p>
            </div>}
        </div>
      </a>
    </div>;
};

Verify signatures from signed messages to authenticate users or validate transactions using CosmJS.

## Prerequisites

<Card title="Setup CosmJS Libraries" description="Configure CosmJS with Para SDK first" href="/v2/react/guides/web3-operations/cosmos/setup-libraries" icon="gear" horizontal />

## Verify Signatures

Verify ADR-036 signatures using CosmJS crypto utilities.

```typescript theme={null}
import { useState } from "react";
import { fromBase64, toUtf8 } from "@cosmjs/encoding";
import { Secp256k1, Secp256k1Signature, sha256 } from "@cosmjs/crypto";
import { serializeSignDoc, makeSignDoc } from "@cosmjs/amino";

function SignatureVerification() {
  const [isValid, setIsValid] = useState<boolean | null>(null);

  const verifyADR036Signature = async () => {
    const pubkeyBase64 = "A08EGB7ro1ORuFhjOnZcSgwYlpe0DSFjVNUIkNNQxwKQ";
    const signatureBase64 = "..."; // Signature from signAmino
    const originalMessage = "Hello Para!";
    const signerAddress = "cosmos1...";
    const chainId = "cosmoshub-4";

    try {
      const pubkey = fromBase64(pubkeyBase64);
      const signature = fromBase64(signatureBase64);

      const signDoc = makeSignDoc(
        [{ type: "sign/MsgSignData", value: { signer: signerAddress, data: btoa(originalMessage) } }],
        { amount: [], gas: "0" },
        chainId,
        "",
        0,
        0
      );

      const serialized = serializeSignDoc(signDoc);
      const messageHash = sha256(serialized);

      const sig = Secp256k1Signature.fromDer(signature);
      const valid = await Secp256k1.verifySignature(sig, messageHash, pubkey);

      setIsValid(valid);
      console.log("Signature valid:", valid);
    } catch (error) {
      console.error("Verification failed:", error);
      setIsValid(false);
    }
  };

  return (
    <div>
      <button onClick={verifyADR036Signature}>Verify Signature</button>
      {isValid !== null && <p>Valid: {isValid ? "Yes" : "No"}</p>}
    </div>
  );
}
```

## Next Steps

<CardGroup cols={3}>
  <Card title="Sign Messages" description="Create signatures for verification" href="/v2/react/guides/web3-operations/cosmos/sign-messages" icon="signature" />

  <Card title="Execute Transactions" description="Send verified transactions" href="/v2/react/guides/web3-operations/cosmos/execute-transactions" icon="bolt" />

  <Card title="Query Balances" description="Check account balances" href="/v2/react/guides/web3-operations/cosmos/query-balances" icon="wallet" />
</CardGroup>