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Documentation Index

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Use decryptForView to reveal a confidential (encrypted) value locally in your app so you can display it in the UI. Unlike decryptForTx, this flow does not return an on-chain-verifiable signature, and it is not meant to be published on-chain.

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Flow

  1. Read the encrypted handle (ctHash) from your contract.
  2. Ensure you have a permit that authorizes decryption of that value.
  3. Call decryptForView(ctHash, utype).execute() to get the plaintext.
decryptForView always decrypts using a permit (there is no .withoutPermit() mode). If your protocol intends for the plaintext to become publicly visible on-chain, use decryptForTx instead.

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Prerequisites

  1. Create and connect a client.
  2. Know the encrypted handle (ctHash) and the encrypted type (utype).
  3. Have a permit available for the connected chainId + account.
Getting ctHash: In most apps, ctHash comes from reading a stored encrypted value, an event arg, or a return value from a view call.
Providing utype: utype must match the ciphertext’s underlying FHE type. The SDK uses it to convert the decrypted bigint into a convenient JS type.Supported utypes:
  • FheTypes.Bool → returns a boolean
  • FheTypes.Uint160 (address) → returns a checksummed 0x... string
  • FheTypes.Uint8 | Uint16 | Uint32 | Uint64 | Uint128 → returns a bigint

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Permit setup

If you don’t have a permit yet, create one once after connecting: 
await client.connect(publicClient, walletClient);

// Creates a permit if needed, stores it, and selects it as the active permit.
await client.permits.getOrCreateSelfPermit();

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Decrypt for UI

Choose the pattern that matches how your app manages permits: 
await client.connect(publicClient, walletClient);
await client.permits.getOrCreateSelfPermit();

const plaintext = await client
  .decryptForView(ctHash, FheTypes.Uint32)
  .execute();

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What decryptForView returns

Running .execute() resolves to a scalar JS value:
  • Integer utypes (Uint8, Uint16, Uint32, Uint64, Uint128): a bigint
  • FheTypes.Bool: a boolean
  • FheTypes.Uint160 (address): a checksummed 0x... address string

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Builder API

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.execute() — required, call last

Runs the decryption and returns a UI-friendly scalar value.

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.withPermit(...) — optional

Select which permit to use:
  • .withPermit() — uses the active permit
  • .withPermit(permitHash) — fetches a stored permit by hash
  • .withPermit(permit) — uses the provided permit object
If you don’t call .withPermit(...), the active permit is used by default.

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.setAccount(address) — optional

Overrides the account used to resolve the active/stored permit.

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.setChainId(chainId) — optional

Overrides the chain used to resolve the Threshold Network URL and permits.

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Common UI patterns

import { formatUnits } from 'viem';

const decimals = 6;
const display = formatUnits(amount, decimals);

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Common pitfalls

  • Missing permit: decryptForView will fail if there is no active permit for the current chainId + account.
  • Wrong utype: you must pass the correct FHE type for the ciphertext.
  • Wrong chain/account: permits are scoped to chainId + account. If the user switches wallets or networks, create/select the correct permit.