diff --git a/src/verifications.js b/src/verifications.js
index 7b682ce..f54d04c 100644
--- a/src/verifications.js
+++ b/src/verifications.js
@@ -89,7 +89,7 @@ const containsProof = async (data, params) => {
             if (parseInt(match[0].split('$')[2]) > 12) continue
 
             const hashPromise = bcryptVerify({
-              password: fingerprintURI,
+              password: fingerprintURI.toLowerCase(),
               hash: match[0]
             })
               .then(result => result)
@@ -102,6 +102,28 @@ const containsProof = async (data, params) => {
           } catch (err) {
             result = false
           }
+
+          // Accept mixed-case fingerprints until deadline
+          if (!result) {
+            try {
+              // Patch until promise.race properly works on WASM
+              if (parseInt(match[0].split('$')[2]) > 12) continue
+
+              const hashPromise = bcryptVerify({
+                password: fingerprintURI,
+                hash: match[0]
+              })
+                .then(result => result)
+                .catch(_ => false)
+
+              result = await Promise.race([hashPromise, timeoutPromise]).then((result) => {
+                clearTimeout(timeoutHandle)
+                return result
+              })
+            } catch (err) {
+              result = false
+            }
+          }
           break
 
         case 'argon2':
@@ -110,7 +132,7 @@ const containsProof = async (data, params) => {
         case 'argon2id':
           try {
             const hashPromise = argon2Verify({
-              password: fingerprintURI,
+              password: fingerprintURI.toLowerCase(),
               hash: match[0]
             })
               .then(result => result)
@@ -123,6 +145,25 @@ const containsProof = async (data, params) => {
           } catch (err) {
             result = false
           }
+
+          // Accept mixed-case fingerprints until deadline
+          if (!result) {
+            try {
+              const hashPromise = argon2Verify({
+                password: fingerprintURI,
+                hash: match[0]
+              })
+                .then(result => result)
+                .catch(_ => false)
+
+              result = await Promise.race([hashPromise, timeoutPromise]).then((result) => {
+                clearTimeout(timeoutHandle)
+                return result
+              })
+            } catch (err) {
+              result = false
+            }
+          }
           break
 
         default:
diff --git a/test/verifications.test.js b/test/verifications.test.js
index 77cfd48..7b2abc8 100644
--- a/test/verifications.test.js
+++ b/test/verifications.test.js
@@ -50,6 +50,8 @@ describe('verifications.run', () => {
   it('should verify a plaintext proof', async () => {
     const result = await verifications.run(plaintextCorrectProofData, claimData, fingerprint)
     expect(result.result).to.be.true
+    const result2 = await verifications.run(plaintextCorrectProofData, claimData, fingerprint.toUpperCase())
+    expect(result2.result).to.be.true
   })
   // issue #22
   it('should handle a plaintext proof with whitespace', async () => {
@@ -63,6 +65,8 @@ describe('verifications.run', () => {
   it('should verify a argon2-hashed proof', async () => {
     const result = await verifications.run(argon2CorrectProofData, claimData, fingerprint)
     expect(result.result).to.be.true
+    const result2 = await verifications.run(argon2CorrectProofData, claimData, fingerprint.toUpperCase())
+    expect(result2.result).to.be.true
   })
   it('should reject a wrong argon2-hashed proof', async () => {
     const result = await verifications.run(argon2IncorrectProofData, claimData, fingerprint)
@@ -71,6 +75,8 @@ describe('verifications.run', () => {
   it('should verify a bcrypt-hashed proof', async () => {
     const result = await verifications.run(bcryptCorrectProofData, claimData, fingerprint)
     expect(result.result).to.be.true
+    const result2 = await verifications.run(bcryptCorrectProofData, claimData, fingerprint.toUpperCase())
+    expect(result2.result).to.be.true
   })
   it('should reject a wrong bcrypt-hashed proof', async () => {
     const result = await verifications.run(bcryptIncorrectProofData, claimData, fingerprint)